MICHAEL DALY HAWKINS, Circuit Judge:

This appeal requires us to examine California tort and products liability law as made specifically applicable to actions in federal court for claims of injury arising out of nuclear power plant incidents. Specifically, we must decide whether the district court erred in (1) refusing to give a jury instruction under Rutherford v. Owens-Illinois, Inc., 16 Cal.4th 953, 67 Cal.Rptr.2d 16, 941 P.2d 1203 (1997), in a ease involving a single defendant who raises alternative possible sources of the injury as a defense; and (2) dismissing claims under California products liability law. For the reasons set forth below, we reverse and remand the case for a new trial.

BACKGROUND

Ellen Kennedy died in 1996 of chronic myelogenous leukemia (“CML”), a rare form of cancer. She was 43 years old. The plaintiffs/appellants are her husband, Joe, and their four children (collectively referred to as “Kennedy”). From 1982 to 1990, Mr. Kennedy worked as machinist for Southern California Edison Company (“Cal Edison”) at the company’s San Onofre Nuclear Generating Station (“SONGS”).

The plaintiffs sued Cal Edison in federal court, asserting jurisdiction pursuant to the Price-Anderson Act, 42 U.S.C. § 2011 et seq., and seeking damages for Ellen Kennedy’s wrongful death. The action alleged that her terminal CML resulted from negligence on the part of Cal Edison that resulted in her exposure to radiation from SONGS. Additionally, Kennedy sued Combustion Engineering, Inc., under a products liability cause of action, for the alleged faulty production of nuclear fuel rods. The theory of the case was that Joe *992Kennedy inadvertently brought home microscopic particles of radioactive material, known as “fuel fleas,” from the power plant on his clothing, hair, tools, etc. These fuel fleas, which according to Kennedy contained radiation dosages in excess of the maximum allowable by federal regulations, came in contact with Mrs. Kennedy and caused her fatal cancer.

On March 20, 1997, the district court granted Combustion Engineering’s motion to dismiss all the products liability claims against it. The court reasoned that, inasmuch as Mrs. Kennedy was not a user or consumer of the nuclear fuel rods Combustion Engineering produced, Combustion Engineering could not have reasonably foreseen that Mrs. Kennedy would be injured by its product.

Kennedy initially sought a burden-shifting order stating that once Kennedy made an initial showing of Mrs. Kennedy’s exposure to radiation from SONGS, Cal Edison and Combustion Engineering would then bear the burden of proving their conduct was not a substantial factor in causing Mrs. Kennedy’s death. On April 2, 1997, the district court denied this request.

In August 1997, the California Supreme Court issued its opinion in Rutherford, a products liability action brought by the estate of a worker who had been exposed to asbestos-containing products and subsequently died of lung cancer. The case, discussed infra, dealt in large part with the proper jury instructions to be given on causation when multiple potential causes of the injury exist. In light of the decision, Kennedy requested a causation instruction “consistent with Rutherford.” On November 14,1997, the district court denied Kennedy’s request. Kennedy requested a Rutherford instruction and submitted a proposal twice more before trial. Both requests were again denied.

On March 6, 1998, after a fact-intensive, five-week trial, the jury returned a unanimous verdict in favor of Cal Edison and Combustion Engineering. On June 9, 1998, the district court denied Kennedy’s motion for a new trial. This appeal followed. We have jurisdiction pursuant to 28 U.S.C. § 1291.

STANDARD OF REVIEW

Jury instructions challenged as a misstatement of the law are reviewed de novo. See City of Long Beach v. Standard Oil Co., 46 F.3d 929, 933 (9th Cir.1995). We review de novo both a dismissal without leave to amend and a dismissal with leave to amend. See, e.g., San Pedro Hotel Co. v. City of Los Angeles, 159 F.3d 470, 477 (9th Cir.1998); Sameena Inc. v. United States Air Force, 147 F.3d 1148, 1151 (9th Cir.1998).

ANALYSIS

As the case was filed in federal district court under the Price-Anderson Act (“Price-Anderson” or the “Act”), our decision is guided solely by the substantive law of California. Price-Anderson provides federal jurisdiction over lawsuits for injuries arising out of a “nuclear incident.”1 Under such “public liability actions,”2 the “substantive rules for decision ... shall be derived from the law of the State in which the nuclear incident involved occurs, unless such law is inconsistent with the provisions of [section 2210].” 42 U.S.C. § 2014(hh).3

*993Enacted in 1957 during the fledgling days of the nuclear power industry, Price-Anderson had a dual purpose: “to protect the public and to encourage the development of the atomic energy industry.” 42 U.S.C. § 2012(i); Duke Power Co. v. Carolina Envtl. Study Group, Inc., 438 U.S. 59, 64, 98 S.Ct. 2620, 57 L.Ed.2d 595 (1978). The Act accomplishes this by providing certain federal licensees with a system of private insurance, Government indemnification, and limited liability for certain nuclear tort claims. See El Paso Natural Gas Co. v. Neztsosie, 136 F.3d 610, 616 (9th Cir.1998), rev’d on other grounds, 526 U.S. 473, 119 S.Ct. 1430, 143 L.Ed.2d 635 (1999); see also S.Rep. No. 218, 100th Cong., 1st Sess. 2 (1987), reprinted in 1988 U.S.C.C.A.N. 1424, 1476, 1477.

Before its amendment in 1988, Price-Anderson provided the federal courts with original and removal jurisdiction only when the accident at issue was “an extraordinary nuclear occurrence” as defined by the Act. See 42 U.S.C. § 2014Q) (defining “extraordinary nuclear occurrence”). Responding to a flurry of lawsuits in federal and state courts generated by the 1979 nuclear accident at Three Mile Island, which was not considered an extraordinary nuclear occurrence, Congress added section 2014(hh) to the Act, thereby providing the federal courts with original and removal jurisdiction for the broader category of “nuclear' incidents.” See Neztsosie, 526 U.S. at 477, 119 S.Ct. 1430.

I. Rutherford Instruction

A. Background and Applicability

The basic contours of California tort law, in the context of medical injuries with multiple possible causes, are outlined in Jones v. Ortho Pharm. Corp., 163 Cal.App.3d 396, 209 Cal.Rptr. 456 (1985). Jones involved cancer allegedly induced as a result of taking a contraceptive pill. The California Court of Appeal stated:

The law is well settled that in a personal injury action causation must be proven within a reasonable medical probability based upon competent expert testimony. Mere possibility alone is insufficient to establish a prima facie case.... A possible cause only becomes “probable” when, in the absence of other reasonable causal explanations, it becomes more likely than not that the injury was a result of its action. This is the outer limit of inference upon which an issue may be submitted to the jury.

Id. at 460.

The Book of Approved Jury Instructions for California (“BAJI”) provides two general instructions on causation for cases involving injuries with multiple potential causes. It was these two instructions— BAJI 3.76 and 3.77 — that the district court provided to the jury, neither of which was objected to by any of the parties. BAJI 3.76 provides a definition for “cause”: “The law defines cause in its own particular way. A cause of injury, damage, loss or harm is something that is a substantial factor in bringing about an injury, damage, loss or harm.” The other standard jury instruction, BAJI 3.77, pertains to multiple causation. It states:

There may be more than one cause of an injury. When conduct of two or more persons or conduct and a defective product contributes concurrently as causes of an injury, the conduct of each is a cause of the injury regardless of the extent to which each contributes to the injury. A cause is concurrent if it was operative at the moment of injury and acted with another cause to produce the injury.

Rutherford addressed the adequacy of these instructions and altered the landscape of California tort law, as it applies to the burden of proof to establish causation for asbestos-induced cancer, when it held that BAJI 3.76 and 3.77 must be augmented by an additional instruction. See 67 Cal.Rptr.2d 16, 941 P.2d at 1223. Though the court reiterated traditional California tort principles on causation and cited Jones’s “reasonable medical probability” *994requirement with approval, see id. at 1214, 1219 n. 1, it cited four factors in asbestos-related cancer cases that necessitated a departure from the standard jury instructions on causation.

First, the court noted that “there is scientific uncertainty regarding the biological mechanisms by which inhalation of certain microscopic fibers of asbestos leads to lung cancer.... ” Id. at 1218. Second, it discussed the uncertainty that “frequently exists” whether a plaintiff was even exposed to dangerous asbestos fibers produced, distributed or installed by a particular defendant. The court was particularly concerned with the long latency periods of asbestos-related cancers and the many different asbestos-containing products that may have been used at the same time and in the same workplace. See id. Third, the court stated that the “question arises whether the risk of cancer created by ... exposure to a particular asbestos-containing product was significant enough to be considered a legal cause of the disease.” Id. Finally, the court noted the “impossibility” of proving “the unknowable path of a given asbestos fiber.” Id. at 1219.

Despite these difficulties of proof, the California Supreme Court rejected the argument that the burden of proving causation should shift to the defendants after the plaintiffs had proven exposure to asbestos-containing products.4 The court reasoned that the fundamental justification for a shifting of the burden' — that without such a shift all defendants might escape liability and the plaintiff be left “remediless” — is absent in asbestos-related cancer cases. Id. at 1220 (quoting Summers v. Tice, 33 Cal.2d 80, 199 P.2d 1, 4 (1948)). Moreover, the court pointed out that in asbestos cases, unlike traditional alternative liability cases, the complete set of possible tortfeasors is not before the court, and that given the wide ranging toxieities of different asbestos-containing products, the tortfeasors that are before the court do not display the “same symmetry of comparative fault or indivisible injury” that-are the trademarks of alternative liability cases. See id. (internal quotations omitted). Having rejected burden-shifting, the California Supreme Court was presented with a Gordian knot of its own making: traditional causation principles presented asbestos-related cancer patients with insuperable barriers to recovery, yet the court had rejected alternative liability as being unsuited for these types of cases.

Rutherford cut the knot by altering, rather than shifting, the plaintiffs burden. The court held that

plaintiffs may prove causation in asbestos-related cancer cases by demonstrating that the plaintiffs exposure to defendant’s asbestos-containing product in reasonable medical probability was a substantial factor in contributing to the aggregate dose of asbestos the plaintiff or decedent inhaled or ingested, and hence to the risk of developing asbestos-related cancer, without the need to demonstrate that fibers from the defendant’s particular product were the ones, or among the ones, that actually produced the malignant growth.

Id. at 1219 (footnote omitted).

The burden now established, the court turned to the standard jury instructions, BAJI 3.76 and 3.77, and found them “insufficient for [the] purpose” of ensuring that jurors know the “precise contours” of this newly-crafted burden. See id. Specifically, the court found that BAJI 3.76 and 3.77

say nothing, however, to inform the jury that, in asbestos-related cancer cases, a particular asbestos-containing product is deemed to be a substantial factor in bringing about the injury if its contribution to the plaintiff or decedent’s risk or *995probability of developing cancer was substantial.

Without such guidance, a juror might well conclude that the plaintiff needed to prove that fibers from the defendant’s product were a substantial factor actually contributing to the development of the plaintiffs or decedent’s cancer. In many cases, such a burden will be medically impossible to sustain, even with the greatest possible effort by the plaintiff, because of irreducible uncertainty regarding the cellular formation of an asbestos-related cancer.

Id. at 1219-20.

To rectify these shortcomings of the standard instructions in asbestos-related cancer cases, the court then held that in addition to BAJI 3.76 and 3.77, the jury must also be instructed that

the plaintiff need not prove that fibers from the defendant’s product were the ones, or among the ones, that actually began the process of malignant cellular growth. Instead, the plaintiff may meet the burden of proving that exposure to defendant’s product was a substantial factor causing the illness by showing that in reasonable medical probability it ivas a substantial factor contributing to the plaintiffs or decedent’s risk of developing cancer.

Id. at 1203 (emphasis added). It is this passage upon which Kennedy based his repeated requests for a Rutherford instruction.

We must now decide whether Rutherford is applicable to the instant case. We hold that it is.

We begin by noting that the California Supreme Court has applied Rutherford to claims involving exposure to substances other than asbestos. In Bockrath v. Aldrich Chemical Co., 21 Cal.4th 71, 86 Cal.Rptr.2d 846, 980 P.2d 398 (1999), it applied Rutherford to a cancer claim based on exposure to multiple workplace chemicals. Accordingly, we find nothing in California’s jurisprudence that would exclude cases of CML after exposure to radioactive particles from Rutherford’s purview.5

The more difficult question is whether Rutherford is applicable in single-defendant cases. For the reasons set forth below, we hold that Rutherford does apply to single-defendant hazardous substance cases where the defense of alternative possible causes is raised.

The limited number of cases applying Rutherford have all involved multiple defendants, and appellees argue that this is a necessary requirement for a Rutherford instruction. We disagree. We find little relevant distinction between a Rutherford case with multiple defendants, each of whose products may have been a substantial factor in causing the plaintiffs injury, and a case in which a single defendant argues that the plaintiff cannot show causation because there exist other potential sources that may have been the legal cause of the harm.

In both circumstances, the plaintiff is faced with the same hurdles that the California Supreme Court identified as making proof of causation, absent the Rutherford instruction, nearly impossible. On a scientific level, the uncertainty regarding the biological mechanisms by which asbestos leads to lung cancer, see Rutherford, 941 P.2d at 1218, parallel the medical uncertainties surrounding the cause and effect relationship between CML and radiation. And, it is just as impossible to prove the course of radiation as it is to prove the “unknowable path of a given asbestos fiber.” Id. at 1219.

More importantly, by choosing to raise alternative sources of the injury as a defense, a defendant creates the need for a Rutherford instruction. Just as the presence of multiple defendants in an asbestos-*996related cancer case raises the question of “whether the risk of cancer created by ... exposure to a particular asbestos-containing product was significant enough to be considered a legal cause of the disease,” id. at 1218, so too does the proffering of alternative causes of CML by a single defendant. In both scenarios a given defendant is making essentially the same argument: the plaintiff cannot prove that his injury came from a specific source (i.e. the defendant), when multiple other potential sources exist, whether they be another asbestos-related defendant or something altogether different, such as cigarette smoking or radiation from the sun in the case of CML.

While the instant case has two defendants, neither argued that the other was an independent source of causation. Their defense raised other possible causes of Mrs. Kennedy’s CML, none of which was attributable to either of the defendants. In essence, then, Cal Edison and Combustion Engineering operated as a single defendant with respect to the issue of alternative causes of the injury.

B. Correctness of Proffered Instruction and Obligation of the District Court

Having held that a Rutherford instruction was required, we now turn to the specific instruction proffered by Kennedy. At oral argument, appellees argued that the requested instruction was not a proper Rutherford instruction. We agree.

On two occasions, Kennedy proposed the following instruction, that was to be inserted between BAJI 3.76 and BAJI 3.77:

In order to prove that radiation from the nuclear power plant was a substantial factor, Plaintiffs do not need to prove that it actually contributed to the development of Ellen Marie Kennedy’s cancer. If exposure to radiation from the nuclear power plant in reasonable medical probability contributed to her risk of developing cancer then such exposure was a substantial factor in causing her cancer.

The proposed instruction leaves out a small, but critical, phrase. It states that radiation from SONGS need only have “contributed” to Mrs. Kennedy’s risk of developing cancer. We read Rutherford to require more. Kennedy’s burden is not to show that exposure to radiation in reasonable medical probability “contributed” to a risk of cancer. Rather, it is to demonstrate that the exposure in reasonable medical probability was “a substantial factor” in contributing to the risk of cancer. The omission of this modifier is essential to a proper Rutherford instruction.

That the defendant’s product must, in reasonable medical probability, be a “substantial factor” in contributing to the risk of cancer was reiterated as necessary to the instruction three times by the Rutherford court. See id. at 1219 (stating that a plaintiff may prove causation by showing that exposure to defendant’s asbestos-containing product “in reasonable medical probability was a substantial factor in contributing to the ... risk of developing asbestos-related cancer”) (emphasis added); id. at 1220 (“[T]he jury should be told that the plaintiffs or decedent’s exposure to a particular product was a substantial factor in causing or bringing about the disease if in reasonable medical probability it was a substantial factor contributing to plaintiffs or decedent’s risk of developing cancer.”) (emphasis added); id. at 1223 (“In conclusion ... the plaintiff may meet the burden of proving that exposure to defendant’s product was a substantial factor causing the illness by showing that in reasonable medical probability it was a substantial factor contributing to the plaintiffs or decedent’s risk of developing cancer. The jury should be so instructed.”) (emphasis added).

Our focus on the “substantial factor” language is not mere quibbling over linguistic technicalities. Although “substantial factor” has not been explicitly defined by the California courts, Bockrath, quoting *997extensively from Rutherford, the broad outlines of the term: delineated

The substantial factor standard is a relatively broad one, requiring only that the contribution of the individual cause be more than negligible or theoretical. Thus, a force which plays only an “infinitesimal’ ” or “ ‘theoretical’ ” part in bringing about injury, damage, or loss is not a substantial factor, but a very minor force that does cause harm is a substantial factor

Bockrath, 86 Cal.Rptr.2d 846, 980 P.2d at 408 (internal citations and quotations omitted). The omission of the “substantial factor” language from Kennedy’s requested instruction, therefore, would have enabled the jury to have found that radiation from SONGS was the legal cause (i.e., a substantial factor in bringing about the injury, see supra BAJI 3.76), of Mrs. Kennedy’s death, even if the radiation played only an “infinitesimal” or “theoretical” part in contributing to her risk of CML. Such a result is inconsistent with Rutherford.

That the proposed instructions were not entirely correct under Rutherford is insufficient to affirm the district court’s refusal to instruct the jury properly. Ordinarily, a district court does not err in refusing to give incorrect or misleading instructions. See, e.g., Mitchell v. Keith, 752 F.2d 385, 388 (9th Cir.1985).

A district court, however, may have an obligation to correctly instruct the jury even after being presented with an arguably improper instruction that nonetheless directs its attention to an important issue. While this issue has not been expressly decided in this circuit, several of our sister circuits have held that such an obligation does exist. See Webster v. Edward D. Jones & Co., L.P., 197 F.3d 815, 820 (6th Cir.1999) (“Even if an incorrect proposed instruction is submitted which raises an important issue of law involved in light of proof adduced in the case, it becomes the duty of the trial court to frame a proper instruction on the issue raised.... ”); Wilson v. Maritime Overseas Corp., 150 F.3d 1, 10 (1st Cir.1998) (“If the request directs the court’s attention to a point upon which an instruction to the jury would be helpful, the court’s error in failing to charge may not be excused by technical defects in the request.”) (quoting 9A Charles A. Wright & Arthur R. Miller, Federal Practice and Procedure § 2552 at 395-97 (1995)); Bueno v. City of Donna, 714 F.2d 484, 490 (5th Cir.1983) (“So long as an inadequate or improper request is sufficient to direct the court’s attention to a legal defense, the court is thereby alerted that a proper instruction is required.”); Brandes v. Burbank, 613 F.2d 658, 668 (7th Cir.1980) (“Even though the tendered instruction is not entirely perfect, there are situations where the court is not relieved of its duty to give the substance of the requested instruction where it appears that an instruction on the issue is needful to enable the jury to determine intelligently the question”); Posttape Assocs. v. Eastman Kodak Co., 537 F.2d 751, 757 (3d Cir.1976) (“[I]f an important issue is timely called to [a trial judge’s] attention, he should instruct the jury on that matter.”); Chavez v. Sears, Roebuck & Co., 525 F.2d 827, 830 (10th Cir.1975) (“Since the trial court bears the ultimate responsibility for properly instructing the jury, we agree with those courts that have ruled that where an instruction would be beneficial to the jury’s proper determination of the case, the court may not merely refuse a requested instruction, but instead has a duty to frame the instruction properly and give it to the jury.”); Emery v. Northern Pac. R.R. Co., 407 F.2d 109, 113 n. 3 (8th Cir.1969) (“If the request directs the court’s attention to a point upon which the jury has not been charged but upon which an instruction would be helpful, the court’s error in failing to charge may not be excused by technical defects in a request to charge.”) (internal quotation omitted).

In Ursich v. da Rosa, 328 F.2d 794, 797 (9th Cir.1964), we held that a district court “was under no obligation to redraw” an incorrect, yet otherwise applicable jury in*998struction for the requesting party. The holding of Ursich was limited by its circumstances. We specifically noted that the requested instruction concerned an “old rule,” the doctrine of res ipsa loquitor, and that we “expect[ed] counsel to be aware of it and to frame proper instructions .... ” Id. n. 1. The instant case, however, presents a much different scenario. Kennedy requested an instruction based on a “new rule” of state law, one that was only a few months old and had yet to be interpreted or applied by any other court.

Moreover, in a case subsequent to Ur-sich, we implicitly recognized that a trial court may have the obligation to correct improperly requested jury instructions. In Washington State Bowling Proprietors Ass’n v. Pacific Lanes, Inc., 356 F.2d 371, 376-77 (9th Cir.1966), we stated that “we do not suggest a trial court is under no obligation to charge on a material issue after requested to do so, even if the instructions as proposed are faulty....”6

Today we make explicit what Pacific Lanes suggested, and align this circuit with the majority of our sister circuits. We hold that when the district court is presented with an applicable instruction that raises an important issue of law or directs the court’s attention to a point upon which an instruction to the jury would be important, it is not relieved from the responsibility of giving a proper instruction simply because the party making the request has proposed an instruction that does not completely comply with the relevant law.7

C. Harmless Error Analysis

Harmless-error review applies to jury instructions in a civil case. See, e.g., Caballero v. City of Concord, 956 F.2d 204, 206 (9th Cir.1992) (“An error in instructing the jury in a civil case requires reversal unless the error is more probably than not harmless.”). This review is “less stringent” than review for harmless error in a criminal case, but “more stringent” than review for sufficiency of the evidence. See id. at 207; City of Long Beach, 46 F.3d at 933 (citing Caballero). In review of civil jury instructions for harmless error, unlike review under sufficiency of the evidence, the “prevailing party is not entitled to have disputed factual issues resolved in his favor because the jury’s verdict may have resulted from a misapprehension of the law rather than from factual determinations in favor of the prevailing party.” Caballero, 956 F.2d at 207 (emphasis added).

We hold the district court’s failure to give a proper Rutherford instruction was not harmless error. “An error in a trial court’s jury instructions relating to the parties’ respective burdens of proof ordinarily [requires] reversal.” Larez v. Holcomb, 16 F.3d 1513, 1518 (9th Cir.1994). But see Mockler v. Multnomah County, 140 F.3d 808, 812-814 (9th Cir.1998) (improper instruction on plaintiffs burden of proof held harmless when evidence would support verdict for plaintiff in any event).

Appellees argue that Kennedy failed to establish that any type of radiation — and not just radiation from SONGS — actually caused Mrs. Kennedy’s CML. This argument is based on the contention that the testimony of Kennedy’s expert — that more than 90% of CML cases are caused by radiation — was a personal belief that was *999unsupportable and contrary to the consensus view of the scientific community.

Cal Edison and Combustion Engineering, however, did not contest the admission of this testimony under the Federal Rules of Evidence, nor did they present a challenge to the testimony under Daubert v. Merrell Dow Pharmaceuticals, Inc., 509 U.S. 579, 113 S.Ct. 2786, 125 L.Ed.2d 469 (1993). Because the jury was not presented with any special verdicts or interrogatories, there is no way of knowing the grounds upon which it based its decision. The harmless error analysis does not entitle appellees to have disputed factual issues resolved in their favor. The possibility exists, therefore, that the jury could have found the expert testimony credible, yet still found for the appellees on the basis of the erroneous causation instructions. Accordingly, the failure to give a Rutherford instruction cannot be harmless error.

Alternatively, Cal Edison and Combustion Engineering argue that even if a Rutherford instruction were given, Kennedy failed to produce enough evidence proving that radiation from SONGS was a substantial factor in contributing to Mrs. Kennedy’s risk of CML. In particular, Cal Edison and Combustion Engineering correctly note that their experts provided un-contradicted testimony that, even if Mrs. Kennedy was exposed to radiation from SONGS, there was only a one in one hundred thousand chance that this radiation caused her CML. The failure to give the Rutherford instruction, they argue, was therefore harmless error.

Under the jury instructions as given, in order to sustain their burden of proof Kennedy needed to have proven by a preponderance of the evidence that the radiation from SONGS was a “substantial factor” in causing Mrs. Kennedy’s CML. In Rutherford, the California Supreme Court cautioned that “[ujndue emphasis should not be placed on the term ‘substantial.’ ” Rutherford, 67 Cal.Rptr.2d 16, 941 P.2d at 1214. As discussed above, this standard only requires that the contribution of the individual cause be more than negligible or theoretical. See id. at 1219.

Under a preponderance of the evidence standard, the jury is only required to believe that “the existence of a fact is more probable than its nonexistence.” Concrete Pipe and Prods. of Cal., Inc. v. Construction Laborers Pension Trust for So. Cal., 508 U.S. 602, 622, 113 S.Ct. 2264, 124 L.Ed.2d 539 (1993). Therefore, all the jury need have concluded, if given a Rutherford instruction, was that it was more probable than not that there was more than a negligible probability that Mrs. Kennedy’s cancer was caused by radiation from SONGS. We believe the jury could have reasonably so found.

It would not be unreasonable for a juror to conclude that a one in one hundred thousand chance of developing a fatal cancer was more than a mere theoretical possibility. Presented perhaps more concretely, if the entire U.S. population were exposed to the amount of radiation in ap-pellee’s hypothetical upon which its expert based his statistical opinion, then approximately 2,500 people would contract CML. While this number is relatively small, it is more than “negligible.”8

*1000II. Products Liability Claims

Under California products liability law, “a manufacturer may be held strictly liable in tort for placing a defective product on the market if that product causes personal injury, provided that the injury resulted from a use of the product that was reasonably foreseeable by the defendants. This doctrine of strict liability extends to products which have design defects, manufacturing defects, or warning defects.” Sparks v. Owens-Illinois, Inc., 32 Cal.App.4th 461, 38 Cal.Rptr.2d 739, 745 (1995) (internal quotation and citation omitted). “Manufacturers of defective products are liable for injuries not only to the purchaser or user of such products, but to injured bystanders as well.... ” Barrett v. Superior Court, 222 Cal.App.3d 1176, 272 Cal.Rptr. 304, 309 (1990).

We first note that strict liability can be consistent with Price-Anderson. It is relatively well-settled that federal regulations provide the sole measure of a defendant’s duty under Price-Anderson. See, e.g., Roberts v. Florida Power & Light Co., 146 F.3d 1305, 1308 (11th Cir.1998) (citing cases from the Seventh, Sixth, and Third Circuits). This is because the “states are precluded from regulating the safety aspects of nuclear power,” Silkwood v. Kerr-McGee, Inc., 464 U.S. 238, 240-241, 104 S.Ct. 615, 78 L.Ed.2d 443 (1984), as such safety is “the exclusive business of the federal government.” Pacific Gas & Elec. Co. v. State Energy Resources Conservation & Dev. Comm’n, 461 U.S. 190, 208, 103 S.Ct. 1713, 75 L.Ed.2d 752 (1983).

Strict liability would only be inconsistent with Price-Anderson, then, if a specific claim would enable a plaintiff to recover from a defendant in a public liability action under the Act without first establishing that the defendant breached a federally imposed duty of care. See Roberts, 146 F.3d at 1308 (affirming district court dismissal of strict liability and negligence claims on grounds that plaintiffs did not allege that defendant exposed them to radiation in excess of the maximum allowable by federal regulations).

More importantly, the Supreme Court itself has contemplated strict liability actions under Price-Anderson. In Silkwood, 464 U.S. at 256, 104 S.Ct. 615, the Court noted the tension between “the conclusion that safety regulation is the exclusive concern of the federal law and the conclusion that a state may nevertheless award damages based on its own law of liability.” The Court found, however, that “Congress intended to stand by both concepts and to tolerate whatever tension there was between them.” Id. The Court concluded that “[i]t may be that the award of damages based on the state law of negligence or strict liability is regulatory in the sense that a nuclear plant will be threatened with damages liability if it does not conform to state standards, but that regulatory consequence was something that Congress was quite willing to accept.” Id. (emphasis added).

Finding the application of strict products liability consistent with Price-Anderson, we consider the merits of the plaintiffs’ claims. As we noted in our discussion of their claims against SONGS, the plaintiffs have presented evidence that Mrs. Kennedy’s cancer was caused by exposure to radioactive “fuel fleas” released from Combustion Engineering’s apparently defective fuel rods and carried home on her husband’s clothing. Despite this showing, Combustion Engineering argues that it was entitled to summary judgment on strict liability because it never marketed the fuel rods to the public, and because it could not have foreseen that the rods would injure a nonemployee of SONGS like Mrs. Kennedy.

*1001California imposes strict products liability only for injuries caused by defective products that a manufacturer or distributor “places on the market.” Greenman v. Yuba Power Prods., Inc., 59 Cal.2d 57, 27 Cal.Rptr. 697, 377 P.2d 897, 900 (1963) (en banc) (Traynor, J.). To place a product on the market is to “play an integral role in the ‘producing and marketing enterprise’ of a defective product and [to] profit from placing the product into the stream of commerce.” Bay Summit Community Ass’n v. Shell Oil Co., 51 Cal.App.4th 762, 59 Cal.Rptr.2d 322, 328 (1996); see Price v. Shell Oil Co., 2 Cal.3d 245, 85 Cal.Rptr. 178, 466 P.2d 722, 727-28 (1970); Mancuso v. Southern Cal. Edison Co., 232 Cal.App.3d 88, 283 Cal.Rptr. 300, 305 (1991) (“Placing an article on the market under the Greenman test is the functional equivalent of putting a product in the stream of commerce .... ” (quotations omitted)).

California has recognized three exceptions to this broad rule. First, a party that plays only a minimal role in the manufacture or distribution of a defective product is not deemed to have placed the product on the market. See Bay Summit, 59 Cal.Rptr.2d at 330. Second, a product is not placed on the market when it does not enter the stream of commerce by means of a commercially significant market transaction. See Mancuso, 283 Cal.Rptr. at 308. And third, a party does not place a product on the market by disposing of it in a unique or isolated transaction. See Price, 85 Cal.Rptr. 178, 466 P.2d at 728.

Though only the last exception arguably applies here, the thread that binds all three together is the “paramount policy” of strict products Lability: “the protection of otherwise defenseless victims of manufacturing defects and the spreading throughout society of the cost of compensating them.” Price, 85 Cal.Rptr. 178, 466 P.2d at 725-26; see Carlin v. Superior Court, 13 Cal.4th 1104, 56 Cal.Rptr.2d 162, 920 P.2d 1347 (1996); Greenman, 27 Cal.Rptr. 697, 377 P.2d at 901. In the case of isolated trafficking in defective goods, the loss-spreading rationale that underlies strict products liability simply does not apply. See Vaerst v. Tanzman, 222 Cal.App.3d 1535, 272 Cal.Rptr. 503, 505-06 (1990); see also Galindo v. Precision American Corp., 754 F.2d 1212, 1218-19 (5th Cir.1985) (“It is clear that the rationale for imposition of strict liability is served only if the defendant is in the business of releasing products into the stream of commerce.”); Restatement (Second) of Torts § 402A, cmt. f (1965) (“The basis [of strict liability] is lacking in the case of the ordinary individual who makes the isolated sale.”).

The market for Combustion Engineering’s products does appear to be narrow, and the consumers of its products few and sophisticated. But no California court has found the loss-spreading rationale of strict products liability inapplicable to the sale of products into a limited market by a firm that is in the business of doing so. California has imposed strict liability on defendants that dealt in defective goods on only a few occasions, see Fakhoury v. Magner, 25 Cal.App.3d 58, 101 Cal.Rptr. 473, 476 (1972) (landlord who leased five furnished apartments strictly liable for defective furniture); Rawlings v. D.M. Oliver, Inc., 97 Cal.App.3d 890, 159 Cal.Rptr. 119, 122 (1979) (manufacturer that produced nine specially-ordered kelp-drying machines strictly liable for defects).

The Restatement gives as examples of isolated transactions exempted from strict liability “the housewife who, on one occasion, sells to her neighbor a jar of jam,” or “the owner of an automobile who, on one occasion, sells it to his neighbor, or even sells it to a dealer in used cars.... ” Restatement § 402A, cmt. f. California has applied the exception in the case of a landlord who leased his own residence on a single occasion, see Vaerst, 272 Cal.Rptr. at 505-06; a one time seller of used manufacturing equipment, see Ortiz v. HPM Corp., 234 Cal.App.3d 178, 285 Cal.Rptr. 728, 733 (1991); and a builder that con*1002structed only two residential homes. See Oliver v. Superior Court, 211 Cal.App.3d 86, 259 Cal.Rptr. 160, 161-62 (1989).

The record suggests that Combustion Engineering has supplied thousands of fuel rods on a continuing basis to SONGS and several other nuclear plants. Combustion Engineering’s enterprise differs entirely in both quality and degree from the ad hoc and infrequent activities to which the isolated transaction exception has been previously deemed applicable. The loss spreading rationale of strict products liability applies to this enterprise with full force. For purposes of strict liability, we conclude that Combustion Engineering has placed its fuel rods on the market.

The “market for which [a product] is produced” also “bears directly upon the issue of foreseeability” of the plaintiffs injury. Dosier v. Wilcox & Crittendon Co., 45 Cal.App.3d 74, 119 Cal.Rptr. 135, 137 (1975) (“ ‘The intended marketing scheme is one basis for deciding which users can be foreseen.’ ”) (quoting Helene Curtis Indus. v. Pruitt, 385 F.2d 841, 860 (5th Cir.1967)). Yet California has not restricted the class of foreseeable plaintiffs to immediate consumers to whom defective products are directly marketed. Rather, California holds “[m]anufaeturers of defective products ... liable for injuries not only to the purchaser or user of such products, but to injured bystanders as well.” Barrett v. Superior Ct., 222 Cal.App.3d 1176, 272 Cal.Rptr. 304, 309 (1990). “[A]n injury to a bystander is often a perfectly foreseeable risk of the maker’s enterprise, and the considerations for imposing such risks on the maker without regard to his fault do not stop with those who undertake to use the chattel.” Elmore v. American Motors Corp., 70 Cal.2d 578, 75 Cal.Rptr. 652, 451 P.2d 84, 89 (1969) (quotations omitted).

In Elmore, the California Supreme Court found that a defective automobile “constitutes a substantial hazard on the highway not only to the driver and passenger of the car but also to pedestrians and other drivers.” Id.

The public policy which protects the driver and passenger of the car should also protect the bystander, and where a driver or passenger of another car is injured due to defects in the manufacture of an automobile and without any fault of their own, they may recover from the manufacturer of the defective automobile.

Id. Since Elmore, California courts have recognized as foreseeable bystanders, employees injured by defective equipment owned or leased by their employers, see Barker v. Lull Eng’g Co., 20 Cal.3d 413, 143 Cal.Rptr. 225, 573 P.2d 443, 457 (1978); Pike v. Frank G. Hough Co., 2 Cal.3d 465, 85 Cal.Rptr. 629, 467 P.2d 229, 235 (1970); Barrett, 272 Cal.Rptr. at 309-10; independent contractors working alongside such employees, see Johnson v. Standard Brands Paint Co., 274 Cal.App.2d 331, 79 Cal.Rptr. 194, 197-98 (1969); a neighbor of a homeowner in whose garage a water heater had been defectively installed, see Hyman v. Gordon, 35 Cal.App.3d 769, 111 Cal.Rptr. 262, 264-65 (1973); an onlooker blinded by debris kicked up by a lawnmower, see Foglio v. Western Auto Supply, 56 Cal.App.3d 470, 128 Cal.Rptr. 545 (1976); and a parking lot attendant struck by a customer’s rolling car. See Preissman v. Ford Motor Co., 1 Cal.App.3d 841, 82 Cal.Rptr. 108, 113 (1969).

These examples are not exhaustive of the circumstances in which injury to a bystander by a defective product may be foreseeable. “[T]he question of foreseeability of injury is an issue for the trier of fact” to be considered on the particular facts of each case. Johnson, 79 Cal.Rptr. at 198; see also Dosier, 119 Cal.Rptr. at 137. It is therefore unavailing to distinguish cases imposing strict liability for defective products sold to employers as having involved injuries to employees, and not employees’ family members. California strict liability turns on actual foreseeability of injury to the plaintiff in the circum*1003stances of a particular case, and not on categorical distinctions among bystanders based on their relationship to the immediate consumer of the defective product. See Johnson, 79 Cal.Rptr. at 198 ("Under the strict liability tort theory, where notions of privity have no part, the bystander could probably recover if injury to him was foreseeable under generally applicable tests." (quotations omitted)); see also Elmore, 75 Cal.Rptr. 652, 451 P.2d at 88-89 (foreseeabiity of bystanders is not restricted by privity of contract with seller of defective goods); Greenman, 27 Cal.Rptr. 697, 377 P.2d at 900 (same).

On the facts of this case, it is perfectly reasonable to conclude that the spouse of a nuclear-plant worker might fall within the foreseeable zone of danger posed by Combustion Engineering's products. There was evidence that due to defects in manufacture, over one hundred Combustion Engineering fuel rods used in the SONGS 3 reactor tended to rupture and disintegrate when brought up to power, releasing microscopic bits of radioactive matter. A SONGS site management memorandum suggests that particular features of these "fuel fleas" made them especially prone to being transported off-site on skin and clothing:

Since they are tiny (normally invisible to the naked eye) dry particles, they do not cling to most surfaces as tenaciously as normal contamination and can be carried short distances on surfaces and then dropped. This intensifies contamination spread problems.

Whether a defect that releases such particles poses a foreseeable risk to family members of workers who are exposed to them is at least a question of fact on which reasonable people may differ, and thus should have been presented to the jury. It was error for the district court to decide the question as a matter of law.

III. Suggestions on Remand

As we noted, the jury was not presented with special verdicts or interrogatories, creating difficulties on appellate review. Had we known the basis upon which the jury made its determination-either that Kennedy had not proven exposure to radiation from SONGS, or that such exposure, though proven, was not the legal cause of Mrs. Kennedy's death-our disposition of the case would have been greatly facilitated.

While we are not prescribing a set of jury instructions, we highlight that proof of exposure is a predicate requirement of Rutherford. Proof of exposure was not at issue in Rutherford, as the case was conducted in a bifurcated trial. Nonetheless, the California Supreme Court made clear that exposure to the allegedly harmful substance must be proven. First, the court noted that in only one instance-where hundreds of manufacturers had made the same drug using an identical formula-have toxic tort plaintiffs been relieved of the burden of proving exposure. See 941 P.2d at 976.

More importantly, the court explicitly indicated that proof of exposure was still a part of a plaintiffs burden under the newly-established rule. At the end of its discussion on the causation issue, the court reiterated the requirements of a Rutherford instruction:

In conclusion, our general holding is as follows. In the context of a cause of action for asbestos-related injuries, the plaintiff must first establish some threshold exposure to the defendant's asbestos-containing products ..

Id. at 982 (emphasis added). Given the language of Rutherford and the inherent difficulties in a general verdict for situations like the instant case, the district court, on remand, may want to consider presenting the jury with a form of verdict that will allow a reviewing court, as well as the parties, to be assured that the requirements of Rutherford have been met.

The decision of the district court is REVERSED, and the case is REMANDED for a new trial consistent with this opinion.

OPINION OF THE COURT

BECKER, Circuit Judge.

The plaintiff, the Lansford-Coaldale Joint Water Authority (“Authority”), provides public water in Carbon County, Pennsylvania. The Authority’s groundwater production and supply wells are adjacent to a site formerly used for lead smelting that is owned by Tonolli Pennsylvania (“Tonolli PA”). After learning that there had been releases of hazardous substances on the Tonolli site and that Tonolli PA had applied for a hazardous waste disposal permit, the Authority commissioned a study to determine whether there was or would be any contamination of its wells. Based on this study, the Authority brought suit against Tonolli PA, its sister corporation, Tonolli Canada, and its parent corporation, IFIM, alleging that they were owners or operators of the Tonolli PA facility and that hazardous discharges from their property posed a threat of future contamination to the Authority’s water supply. Because Tonolli PA had become bankrupt, the Authority subsequently dropped its claims against it, and the trial proceeded against only Tonolli Canada and IFIM. The Authority’s suit sought to recover response costs under the Comprehensive Environmental Response, Compensation and Liability Act (CERCLA), 42 U.S.C. § 9607(a). More specifically, the Authority sought to obtain both the costs it would incur due to the threat of future contamination, e.g., the costs of obtaining an alternative water supply, and the costs it would incur in monitoring and evaluation. At the conclusion of the trial, the district court made oral findings of fact and conclusions of law denying the Authority recovery on all claims. This appeal followed.

At the heart of the Authority’s appeal is an attack on the district court’s fact findings. First, the Authority asserts that the findings are tainted because they were made orally only a few hours after a long and complex trial and were principally drawn verbatim from Tonolli Canada’s proposed findings. Second, the Authority contends that the district court’s finding that the hazardous waste releases at the Tonolli site posed no threat to the Authority’s water supply, which was based upon a finding of hydrogeologic separation of the Tonolli site from the Authority site, was clearly erroneous. Third, the Authority contends that, even if that finding is upheld, we should reverse the district court’s failure to authorize recovery of monitoring and evaluation costs against Tonolli Canada because it was the owner or operator of the Tonolli PA facility.

We acknowledge that the district court might have made more precise findings had it taken the time to await the trial transcript and to draft a written opinion. Moreover, the findings might have been better had they not drawn so heavily on Tonolli Canada’s proposed findings. But the court’s oral findings offered the distinct advantage of fresh recollection and prompt justice. We therefore reject the Authority’s suggestion that the court’s findings are deficient because of the nature of their construction and delivery and hold that they did not violate the requirements of Fed.R.Civ.P. 52(a). Pursuant to that rule, we review them only for clear error.

On the most important issue to the parties, the threat posed to the Authority’s water supply, the district court was faced with a “battle of the experts.” It found Tonolli Canada’s expert more credible than the Authority’s expert and we are satisfied that the court’s findings on this claim are not clearly erroneous.

However, we will vacate the district court’s judgment on the monitoring and evaluation costs claim against Tonolli Canada. In reaching its conclusion that Tonolli Canada should not be deemed an operator, the district court applied the correct inquiry for determining whether Tonolli Canada was a CERCLA operator, i.e., whether it actively participated in the management of the affiliated corporation during a period of hazardous waste disposal. The federal courts are divided over this issue, but we hold that this *1213represents the correct standard. Nevertheless, due to the district court’s failure to address several critical factual issues, we will vacate the judgment on this count and remand for more detailed fact findings.

Finally, the Authority contends that the district court improperly granted judgment in favor of the parent corporation, IFIM, which never filed an answer or otherwise appeared in this case. We will affirm the judgment in favor of IFIM on the Authority’s claim for the costs of obtaining a new water supply and/or treating its current supply because such a result is dictated by the rule prohibiting inconsistent judgments. However,- with respect to the judgment in favor of IFIM on the monitoring and evaluation costs claim, because the district court provided no explanation for its decision and we can discern no basis for it, we will vacate this portion of the judgment and remand to the district court for further consideration.

I. BACKGROUND FACTS AND PROCEDURAL HISTORY

Tonolli Canada is a Canadian Corporation engaged in the business of lead smelting and metal reclamation. In the early 1970’s, To-nolli Canada decided to open a smelting facility in the northeastern United States to reduce transportation costs and improve customer service. It chose a site near Nesqu-ehoning, Carbon County, Pennsylvania. To-nolli PA was incorporated to construct and operate the facility, and Tonolli Canada was its sole shareholder from its incorporation in 1972 until 1976. In 1976, IFIM, a Dutch corporation, purchased all of the Tonolli PA stock and also became the parent corporation of Tonolli Canada. The Nesquehoning plant commenced operations in 1975. The plant site is located approximately 3,100 feet from the Authority’s production wells.

In the early 1980’s, the Authority learned through a public announcement that Tonolli PA had applied for a permit to dispose of hazardous waste at the Nesquehoning site. The parties have also conceded that Tonolli PA was responsible for the release of hazardous substances there, although it is unclear from the record as to when these releases occurred and when the Authority became aware of them. In any event, sometime after learning about the releases as well as Tonolli PA’s permit application, the Authority commissioned a study to determine whether there was or would be any contamination in its wells from the Tonolli site. That study, conducted in July, 1987 and known as the AGES study,1 forms the Authority’s proof regarding a threat of contamination from the Tonolli site.

Although the Authority’s wells are con-cededly upgradient from the Tonolli site, the Authority claims the study shows that continuous pumping of groundwater for a 72-hour period resulted in a reversal in the direction of the groundwater which, if true, means that lead contaminants from the Tonolli site could infiltrate the Authority’s water supply. To-nolli Canada denies that such conclusions can be drawn from the AGES study, and has offered its own expert testimony that the Tonolli discharge did not and cannot affect the Authority’s wells.

The Authority brought suit against Tonolli PA, Tonolli Canada, and IFIM, originally alleging only common law claims, but then adding a claim for private cost recovery under CERCLA. The Authority subsequently dropped its claim against Tonolli PA, which had become bankrupt, so that the trial proceeded against only Tonolli Canada and IFIM. IFIM, however, has never answered or otherwise appeared in the case, although no motion for a default judgment has been made by the Authority. Without explanation, the district court entered judgment in IFIM’s behalf at the close of the trial. The Tonolli Canada submissions advance a procedural argument on behalf of IFIM, but the Tonolli Canada lawyers do not represent IFIM.

The liability phase of the trial took nine days, spread out over December, 1991 and January and February, 1992. Within hours of the conclusion of the trial, the court delivered 150 oral findings, most of which it took verbatim from Tonolli Canada’s proposed findings given to the court at the beginning of the trial.

*1214With respect to the Authority’s more substantial monetary claim — its allegation that releases at the Tonolli site have created a threat of contamination that will cause the Authority either continuously to treat its water supply or to secure a new one — the court found squarely for the defendants. Most importantly, the district court found that the Authority had not proved that there is any threat of future contamination to the Authority’s water supply. However, with respect to the Authority’s claim for monitoring and evaluation costs, the court found that a release at the Tonolli site had induced the Authority to incur monitoring and evaluation expenses (i.e., the costs of the AGES study). The court nonetheless denied recovery for these costs because it concluded that the Authority had not established the other necessary elements of their claim under CERC-LA, specifically, Tonolli Canada’s status as an owner or operator under CERCLA, the necessity of the Authority’s expenses and their consistency with the National Contingency Plan (“NCP”). The district court therefore entered judgment on all counts for Tonolli Canada, and, as noted above, for IFIM. This appeal on the CERCLA issues followed. The disposition of the common law negligence counts has not been appealed.2

II. SCOPE OF REVIEW

Both the Authority and Tonolli Canada agree that the issues that surround the district court’s grant of judgment in favor of Tonolli Canada on both claims present mixed questions of law and fact. The general rule is that we break down the issues into their legal and factual components and engage in plenary review of the legal and factual components and engage in plenary review of the legal components and deferential review of the factual components. See Ram Constr. Co. v. American States Ins. Co., 749 F.2d 1049, 1053 (3d Cir.1984). There is disagreement, however, over the appropriate scope of review of the district court’s factual findings in this case. While ordinarily the factual components are reviewed only for clear error, the Authority contends that the district court’s factual findings here do not satisfy the purposes of Fed.R.Civ.P. 52(a) and hence should not be reviewed under a clearly erroneous standard.

The Authority complains that, despite the complexity of the case, the district court made its findings within a few hours after the trial ended instead of waiting for a transcript and taking the time to reflect and craft a written opinion. It also objects to the court’s having requested proposed findings from the parties only before and not after the trial. These objections seem to us designed more to undermine the substance of the findings themselves than to advance a claim of flawed methodology in their creation. However, the Authority also argues that the district court’s findings are not entitled to deference on appeal because most of them were adopted verbatim from the defendant’s proposed findings of fact.

We reject the Authority’s contention that, because the district court issued its findings orally a few hours after the trial without the benefit of proposed findings submitted by the parties post-trial, the findings do not satisfy the purposes of Fed.R.Civ.P. 52(a). Rule 52(a) expressly authorizes oral findings.3 In fact, in 1983 Rule 52(a) was amended explicitly to sanction the use of oral findings in bench trials. See generally 9 Charles A. Wright, Arthur R. Miller & Frank W. Elliot, Federal Practice & Procedure § 2571, at 225 (Supp.1993). Not only did the district court’s approach not violate the literal language of Rule 52(a), but contrary to the Authority’s argument, it did not violate the spirit of the rule.

*1215We do not deny the force of the Authority’s contention that the district court would have been well-served by requesting the parties to submit proposed factual findings after the close of trial and then articulating its own findings and legal reasoning in a carefully crafted opinion. In many cases this is the more desirable course of action. However, the Authority ignores the benefits of the district court’s approach: by issuing oral findings on the day the trial ended, the district court served the interests of the parties and the legal system in speedy adjudication. See Fed.R.Civ.P. 1. In addition, by announcing its findings soon after the conclusion of the trial, the district court ensured that the record was fresh on its mind, an advantage a court lacks when making findings months later. Furthermore, the overwhelming demands on a district court’s time and resources also affects its ability to prepare extensive findings. For these reasons we reject the Authority’s suggestion that the district court’s oral findings are somehow suspect or tainted.4

We similarly reject the Authority’s argument that the district court’s verbatim adoption of many of Tonolli Canada’s proposed factual findings contravened the purposes of Fed.R.Civ.P. 52(a) such that they do not warrant review under the clearly erroneous standard. This argument has been rejected by the Supreme Court in Anderson v. Bessemer City, N.C., 470 U.S. 564, 105 S.Ct. 1504, 84 L.Ed.2d 518 (1985), in which the Court held that a district court’s findings should receive no less deferential review when the district court announced its decision to the parties first and then asked the prevailing party to prepare findings of fact, many of which it ultimately adopted verbatim. The Court explained that “even when the trial judge adopts proposed findings verbatim, the findings are those of the court and may be reversed only if clearly erroneous.” Id. at 572, 105 S.Ct. at 1510-11.

In addition, we have squarely held that a district court’s findings, when adopted verbatim from a party’s proposed findings, do not demand more stringent scrutiny on appeal. See, e.g., Hayes v. Community Gen. Osteopathic Hosp., 940 F.2d 54, 57 (3d Cir.1991), cert. denied, - U.S. -, 112 S.Ct. 940, 117 L.Ed.2d 110 (1992); Hassine v. Jeffes, 846 F.2d 169, 172 n. 1 (3d Cir.1988); accord Mt. Graham Red Squirrel v. Espy, 986 F.2d 1568, 1571 (9th Cir.1993); 51 James W. Moore, Moore’s Federal Practice ¶ 52.06[1], at 52-127 (1993) (“it is immaterial whether [findings of fact] were drafted by the judge or by counsel”).5 While we cannot dispute that a district court’s verbatim adoption of many of a party’s proposed findings does not always represent a desirable practice, we are satisfied that the district court’s findings here satisfy Rule 52(a) and should be upheld unless they are not supported by the evidence in the record. We note that we found no indication in the record that the district court was unfamiliar with the testimony and exhibits or that it was using the proposed findings as a crutch; if we had, we might view the matter differently. Rather, the record suggests to us that the district court’s *1216findings reflected its informed and considered views.

III. CERCLA LIABILITY FOR THE THREAT OF FUTURE CONTAMINATION

The district court concluded that the Authority had failed to establish that the Tonolli site posed any future threat of contamination to the Authority’s wells. It therefore held that the Authority was not entitled to recover for the costs of procuring an alternative water supply or for continuously treating its existing supply. More fundamentally, in light of its subsidiary factual findings, the court determined that the Tonolli site was hydrogeologically isolated from the Authority’s water production wells so that contamination on the Tonolli property would not migrate to the Authority’s water supply. The Authority challenges this factual conclusion, contending that the evidence adduced at trial overwhelmingly demonstrated that heavy use of the Authority’s wells would draw contamination from the Tonolli site. The Authority submits that the long-term pumping test it conducted, the AGES test, convincingly and unassailably established that there is a hydrogeological connection between the Tonolli site and its production wells and hence that the Tonolli site poses a threat of future contamination to the Authority’s water. In short, the Authority submits that the district court’s factual findings are clearly erroneous. We disagree.

In our view, the district court’s factual determinations are well-supported by the record such that we are not “left with the definite and firm conviction that a mistake has been committed.” United States v. United States Gypsum Co., 333 U.S. 364, 395, 68 S.Ct. 525, 542, 92 L.Ed. 746 (1948). The district court was faced in this case with extensive expert testimony offering conflicting interpretations of the reliability of the Authority’s scientific study and the data it produced. The trial was thus a battle of the experts at the end of which the district court credited the interpretation of Tonolli Canada’s expert rather than that of the Authority. Given that Tonolli Canada’s expert provided a reasonable explanation of the scientific data from the AGES study, we refuse to disturb the district court’s factual conclusions because it is well-established that “[w]here there are two permissible views of the evidence, the factfinder’s choice between them cannot be clearly erroneous.” Anderson v. Bessemer City, N.C., 470 U.S. 564, 574, 105 S.Ct. 1504, 1511, 84 L.Ed.2d 518 (1985). See also Mendes-Silva v. United States, 980 F.2d 1482, 1487 (D.C.Cir.1993) (in a battle of the experts, the factfinder “decide[s] the victor”).

A. The AGES Study

The dispute between Tonolli Canada and the Authority principally revolves around the proper interpretation of the results of the AGES test. In July, 1987, the Authority engaged an engineering firm to perform a long-term pumping test designed to determine whether contamination from the Tonolli property could affect the Authority’s groundwater supply. The Authority then knew (as has been stipulated in this case) that the Authority’s underground water supply was upgradient to the Tonolli site, i.e., the underground area from which the Authority’s wells draw their water is higher than the groundwater area underneath the Tonolli site. Thus, under normal conditions the groundwater does not flow from the Tonolli site toward the Authority’s wells. The Authority undertook the AGES study to see if long-term, continuous pumping of the Authority’s wells would create a reversal of this normal trend such that contamination from the Tonolli site could infiltrate the Authority’s water supply.

The AGES study was conducted over a 72-hour period. The AGES consultants installed three monitoring wells between the Tonol-li site and the Authority’s supply wells. The test also utilized two previously installed monitoring wells located between the Authority’s production wells and the Tonolli site. For the 72-hour period, the Authority pumped its production wells at full capacity and the consultants then took two measurements: 1) the groundwater levels in the To-nolli monitoring wells, and 2) the water quality in the Authority’s production and monitoring wells. According to the Authority, the theory behind this procedure was that if the water level of the Tonolli monitoring wells *1217dropped during the- test, it would tend to prove that long-term and full-scale pumping effected a reversal in groundwater direction. Moreover, if the Authority detected higher levels of contaminants in its wells after the full-scale pumping, this, according to the Authority, would tend to prove that there was a groundwater reversal because the contaminants could have come from the Tonolli site.

At the end of the 72 hours of full-scale pumping there was a drop in two of the Tonolli monitoring wells. The water level in one well dropped by 1.74 feet; in another monitoring well, the water level fell by 1.26 feet. In addition, slightly higher levels of lead and volatile organic compounds (“VOCs”) were detected after the test. The Authority thus argues that the AGES study demonstrated that at some point during the pumping test, the groundwater direction reversed. Dr. Fungaroli, the geologist in charge of the AGES test and the plaintiffs expert witness, testified that based on the results of the AGES study, he believed that the Tonolli site posed a threat of future contamination to the Authority’s current water source.

B. Dr. Earl’s Testimony

The district court’s findings and conclusions are supported by the testimony of the defendant’s expert, Dr. Earl, a hydrogeologist. At the outset, Earl testified that the decreases in water levels in the AGES report were minimal given the scale of the pumping test. Earl testified that the drops in the two monitoring wells after the AGES pumping test may not have been caused by the pumping and do not necessarily suggest that there was a groundwater reversal. Rather, according to Earl, the water level drops could have been caused by a wide variety of factors other than a reversal in groundwater direction. Earl related that there is no way to tell from the AGES study that the water drops were in fact caused by a reversal in groundwater flow and not by these other potential forces.

Earl detailed a number of factors that could account for the drop in the monitoring wells. For example, he testified that seasonal changes or earth tides could have resulted in the water decreases. Earl further testified that changes in sunlight, passage of a cold or warm front, groundwater recharge events (i.e., proximity to streams or lakes where levels are rising and falling), as well as man-made influences such as nearby pumping wells and passing railroad trains, could have caused the water levels to drop as they did. In addition, he stated that some combination of those forces also may have been responsible for the drop in the monitoring wells.

Earl also criticized the AGES study for not observing and recording the trend in water levels in the wells before conducting the pumping test. He stated that the potential causes for the water level decreases that he identified would have been reflected in data about the trend of the wells’ water levels before the test. Earl testified that without this pre-pumping data, there is no way to discern whether it was the pumping test or other factors which caused the drops in the water levels of the monitoring wells. Hence, according to Earl, the AGES pumping test results are inconclusive.

Earl’s testimony raised questions about why the water level dropped, questions that, in his view, could have been answered had the AGES study investigated the pre-pump-ing water level trends in the monitoring wells. In this way, Earl’s testimony provided substantial support for the district court’s conclusion that the Authority had not established by a preponderance of the evidence that the pumping during the AGES test (rather than other factors) caused the water level decreases. The fact that Earl himself did not establish what caused the water levels to drop is inconsequential since Tonolli Canada, as a defendant, did not have the burden of showing the exact cause of the drop in water levels. That burden was on the Authority.

In addition to the questions Earl raised about the conclusiveness of the AGES study, his testimony also provided affirmative support for the district court’s conclusion that the Tonolli site and the Authority’s wells are hydrogeologically isolated. Based on the data used in the AGES study as well as a topographical survey of the area under the *1218Tonolli site conducted by Tonolli Canada, Earl concluded that there is a groundwater divide separating the Tonolli site and the Authority’s wells. Earl also testified that because the Authority’s wells draw their water from a very deep aquifer which is in a discharge zone, the Authority’s wells cannot be contaminated from activity occurring at the surface level.

Earl also raised questions about the Authority’s interpretations of the water quality data gleaned from the AGES study. Specifically, Earl testified that there was no reason to believe that the VOCs and lead detected in the wells after the AGES test came from the Tonolli site. Earl pointed to other possible sources, such as sediments from nearby Tippets Pond and Lake Hauto, which contain lead as demonstrated by samples taken by Tonolli Canada, and which serve as recharge sources for the aquifer that supplies water for the Authority’s wells. Moreover, Earl explained that because there were VOC’s present in the wells before the pumping test even began, there clearly is an upgradient source of VOCs which most likely was the source of the additional VOCs during the full-scale pumping during the AGES test.

We are satisfied that Earl’s testimony regarding the water quality data adequately supports the district court’s finding that the lead and the higher levels of VOC’s did not come from the Tonolli site.6 In addition, Earl’s testimony as to the hydrogeological separation of the Tonolli site also supports the district court’s findings regarding the water quality data, because the hydrogeological separation of the Authority’s wells and the Tonolli site means, by definition, that the higher level of contaminants could not have come from the Tonolli site.7

C. Conclusion

We hold that the district court’s factual finding that the Tonolli site and the Authority’s wells are hydrogeologically isolated is not clearly erroneous.8 We thus uphold the district court’s conclusion that the Authority did not sufficiently demonstrate, through the AGES test, that the Tonolli site poses any threat of contamination to the Authority’s water supply.

IV. MONITORING AND EVALUATION COSTS

A. Background

Although we affirm the district court’s order that there is no threat of future contamination by Tonolli Canada for which the Authority can recover, we must still address the Authority’s doctrinally distinct claim for recovery of its monitoring and evaluation costs. CERCLA authorizes recovery for the costs of “such actions as may be necessary to monitor, assess, and evaluate the release or threat of release of hazardous substances.” 42 U.S.C. § 9601(23). It is well-established that under this provision a plaintiff can re*1219cover its monitoring and evaluation costs from a release or threatened release without proving that its property was actually contaminated by the defendant. See Artesian Water Co. v. Government of New Castle County, 851 F.2d 643, 651 (3d Cir.1988); accord Dedham Water Co. v. Cumberland Farms Dairy, Inc., 889 F.2d 1146, 1153-54 (1st Cir.1989); Wickland Oil Terminals v. Asarco, Inc., 792 F.2d 887, 892 (9th Cir.1986). Even though we uphold the district court’s conclusion that the AGES study failed to establish that the Tonolli site poses any threat of future environmental harm, the Authority may still recover for the costs of the AGES study if it establishes that it incurred these costs in response to a release or threatened release of hazardous material and establishes the other elements of such a CERCLA claim.

CERCLA provides that in order to establish a prima facie case for the recovery of monitoring and evaluation costs, a plaintiff must establish that: 1) the defendant falls into one of four categories of “covered persons,” 42 U.S.C. §§ 9607(a)(1) — (4); 2) there has been a release or a threatened release of a hazardous substance from a facility, 42 U.S.C. § 9607(a)(4); 3) this release or threatened release has caused the plaintiff to incur response costs, 42 U.S.C. § 9607(a)(4); and 4) the plaintiffs response costs are necessary and consistent with the NCP, 42 U.S.C. § 9607(a)(4)(B).

We note that although CERCLA authorizes recovery for monitoring and evaluation costs even when a defendant has not actually contaminated the plaintiffs property, it also provides safeguards to ensure that a defendant will be liable only in situations in which: (1) there was a reasonable risk (although one that may not materialize) that the defendant’s release or threatened release of hazardous substances would contaminate the plaintiffs property; and (2) the monitoring and evaluation expenses were incurred by the plaintiff in a reasonable manner. Because a plaintiff must prove that the defendant was responsible for a release or threatened release of hazardous substances and that the costs incurred in response were both necessary and consistent with the NCP, see 42 U.S.C. § 9607(a)(4), these requirements prevent a plaintiff from recovering the costs incurred in instituting a needless and expensive monitoring study.

The district court held that although both a release and a threatened release of hazardous substances at the Tonolli site caused the Authority to incur monitoring and evaluation costs (the AGES study), the Authority failed to establish the other elements of a prima facie case under CERCLA. Most importantly, the district court concluded that Tonolli Canada did not qualify as a “covered person” under CERCLA, 48 U.S.C. § 9607(a)(1), because it was neither an “owner” nor an “operator” of Tonolli PA. In addition, the district court denied the Authority recovery of its monitoring and evaluation costs because the Authority presented no evidence that the costs it incurred were both necessary and consistent with the NCP.

Tonolli Canada agrees with the district court’s finding that it was neither an owner nor operator of Tonolli PA, but disputes the court’s finding that a release or threatened release of hazardous substances at the Tonol-li site caused the Authority to incur monitoring and evaluation costs. In response, the Authority contends that there was ample evidence supporting the district court’s finding that a release and a threatened release of hazardous material caused it to incur monitoring and evaluation costs, but that the district court’s finding that Tonolli Canada was not an owner or operator of Tonolli PA is clearly erroneous.

B. The Finding that a Release/Threatened Release Caused the Authority to Incur Monitoring and Evaluation Costs

We reject Tonolli Canada’s contention that the district court’s finding that the Authority commissioned the AGES study in response to a release and threatened release of hazardous substances at the Tonolli PA site was clearly erroneous. The district court found that the negligent acts of Tonolli PA caused releases of hazardous substances into the soil at the Tonolli PA facility. It is undisputed that the federal Environmental Protection Agency (EPA) has conducted re*1220moval actions under CERCLA at the Tonolli site due to a release of hazardous substances and is currently conducting a remedial investigation there under CERCLA. In addition, there was testimony at trial that the Authority was concerned about the threat of future releases because Tonolli PA had applied for a permit to dispose of hazardous wastes at its facility. Under this set of circumstances, we cannot say that the district court committed clear error in finding that the Authority, a provider of drinking water to the public, instituted the AGES study, due to releases of hazardous substances and the threat of future releases at the Tonolli site. We thus decline to set aside the finding that a release and a threatened release caused the Authority to incur monitoring and response costs.9

C. “Owner” and “Operator” Status Under CERCLA

1. Background

Although the contours of “owner” and “operator” liability under CERCLA present an issue of first impression for this court, a number of federal courts and commentators have already considered the issue. See, e.g., United States v. Kayser-Roth Corp., 910 F.2d 24 (1st Cir.1990), cert. denied, 498 U.S. 1084, 111 S.Ct. 957, 112 L.Ed.2d 1045 (1991); United States v. Mottolo, 695 F.Supp. 615 (D.N.H.1988); Lynda J. Oswald & Cindy A. Schipani, CERCLA and the “Erosion” of Traditional Corporate Law Doctrine, 86 Nw. U.L.Rev. 259 (1992); Note, Liability of Parent Corporations for Hazardous Waste Cleanup and Damages, 99 Harv.L.Rev. 986 (1986). There is general agreement that under CERCLA, “owner” liability and “operator” liability denote two separate concepts and hence require two separate standards for determining whether they apply. See, e.g., John S. Boyd Co. v. Boston Gas Co., 992 F.2d 401, 408 (1st Cir.1993); Richard B. Stewart & Bradley M. Campbell, Lessons from Parent Liability under CERCLA, 6 Nat. Resources & Env’t 7 (Winter, 1992).

Under CERCLA, a corporation may be held liable as an owner for the actions of its subsidiary corporation in situations in which it is determined that piercing the corporate veil is warranted. See Joslyn Mfg. Co. v. T.L. James & Co., 893 F.2d 80 (5th Cir.1990), cert. denied, 498 U.S. 1108, 111 S.Ct. 1017, 112 L.Ed.2d 1098 (1991). Operator liability, in contrast, is generally reserved for those situations in which a parent or sister corporation is deemed, due to the specifics of its relationship with its affiliated corporation, to have had substantial control over the facility in question.10 ' Courts are divided as to whether operator liability should be predicated on the actual control one corporation has over the other, or whether the corporation’s capacity or authority to control is sufficient. Compare Kayser-Roth, 910 F.2d at 27 (applying “active involvement” test) with Nurad, Inc. v. William E. Hooper & Sons Co., 966 F.2d 837 (4th Cir.) (applying “authority-to-control” test), cert. denied, — U.S. -, 113 S.Ct. 377, 121 L.Ed.2d 288 (1992).

In this case, the district court considered whether Tonolli Canada should be deemed either an owner or an operator under CERC-LA and concluded that neither status applied. The Authority argues that the district court applied incorrect legal standards in deciding these issues and that, in the alternative, even if the district court utilized the correct standards, its conclusions that Tonolli Canada is neither an owner nor an operator áre clearly erroneous. We hold that the district court, by applying the “actual control” test, applied the correct legal standard *1221with respect to the operator liability issue. However, because the district court’s factual findings fail to address a number of key facts relevant to whether or not Tonolli Canada employees exercised control over the affairs of Tonolli PA, we will remand the case to the district court for more detailed fact findings. With respect to owner liability, we conclude that the district court applied the correct standard and properly concluded that Tonolli Canada should not be held liable as an owner. We turn first to the operator liability question because it is the more difficult issue of the two.

2. Operator Liability Under CERCLA

Although congressional intent may be particularly difficult to discern with precision in CERCLA, a statute notorious for its lack of clarity and poor draftsmanship, see Artesian Water Co., 851 F.2d at 649, it is at least clear that Congress has expanded the circumstances under which a corporation may be held liable for the acts of ah affiliated corporation such that, when a corporation is determined to be the operator of a subsidiary or sister corporation, traditional rules of limited liability for corporations do not apply.11 This expansion of Lability is consistent with CERCLA’s broad remedial purposes, most importantly its “essential purpose” of making “those responsible for problems caused by the disposal of chemical poisons bear the costs and responsibiLty for remedying the harmful conditions they created.” John S. Boyd Co., 992 F.2d at 405 (citing Dedham Water Co. v. Cumberland Farms Dairy, Inc., 805 F.2d 1074, 1081 (1st Cir.1986)).

Courts have fashioned two competing standards for the imposition of operator Lability: what we term the “actual control” test and the “authority-to-control” test. Under the actual control standard, a corporation will only be held liable for the environmental violations of another corporation when there is evidence of substantial control exercised by one corporation over the activities of the other, Kayser-Roth Corp., 910 F.2d at 27. In contrast, under the authority-to-control test, operator liability is imposed as long as one corporation had the capability to control, even if it was never utilized. See Nurad, 966 F.2d at 842; Idaho v. Bunker Hill Co., 635 F.Supp. 665, 670-71 (D.Idaho 1986); United States v. Nicolet, Inc., 712 F.Supp. 1193 (E.D.Pa.1989).”

We reject the Authority’s contention that the authority-to-control standard should govern. We believe that test sweeps too broadly and we thus adopt the actual control standard, which appears to strike the appropriate middle ground, balancing the benefits of limited LabLity with CERCLA’s remedial purposes. Under the actual control standard, while the longstanding rule of Lmited liability in the corporate context remains the background norm, a corporation cannot hide behind the corporate form to escape liability in those instances in which it played an active role in the management of a corporation responsible for environmental wrongdoing. In contrast, we believe that a rule which imposes LabLity on a corporation which never exercised its general authority over its subsidiary or sister corporation may unduly penalize the corporation for a decision by that corporation to benefit from one of the well-recognized and salutary purposes of the corporate form: specialization of management, see Frank H. Easterbrook & Daniel R. Fischel, Limited Liability and the Corporation, 52 U.Chi.L.Rev. 89, 90-94. (1985).12

*1222We follow the test adumbrated in Kayser-Roth, supra, and CPC Int’l, Inc. v. Aerojet-General Corp., 777 F.Supp. 549 (W.D.Mich. 1991). As the Kayser-Roth court explained, “[t]o be an operator requires more than merely complete ownership and the concomitant general authority or ability to control that comes with ownership. At a minimum, it requires active involvement in the activities of the subsidiary.” 910 F.2d at 27. Whereas a corporation’s “mere oversight” of the subsidiary or sister corporation’s business in a “manner appropriate and consistent with the investment relationship” does not ordinarily result in operator liability, a corporation’s “actual participation and control” over the other eorporations’s decision-making does. CPC Int’l, 777 F.Supp. at 573.

The determination whether a corporation has exerted sufficient control to warrant imposition of operator liability requires an inherently fact-intensive inquiry, see John S. Boyd Co., 992 F.2d at 408, involving consideration of the totality of the circumstances presented. The factors courts should consider focus on the extent of the corporation’s involvement in the other corporation’s day-to-day operations and its policy-making decisions.13 See CPC Int’l, 777 F.Supp. at 573. We understand the actual control standard to hold accountable for environmental violations those corporations which are not mere investors in other corporations, but instead have actively and substantially participated in the corporation’s management.

In addition, because the essential focus of the actual control test is the control of one corporation over another, not only may a parent corporation be deemed the operator of its subsidiary, but a corporation may also be considered the operator of its sister corporation. In other words, the test is concerned with control rather than ownership and there is no reason not to hold a corporation liable when it exercises substantial management control over an affiliated corporation.

3. Should Tonolli Canada Be Deemed An Operator?

In view of the foregoing discussion, we reject the Authority’s claim that the district court applied the wrong legal standard regarding operator liability, since it expressly applied the actual control test and manifested a correct understanding of it. We therefore review its application of that standard to the facts here for clear error only. See John S. Boyd Co., 992 F.2d at 408; Kayser-Roth, 910 F.2d at 27. Although much of the evidence supports the district court’s conclusion that Tonolli Canada should not be deemed the operator of Tonolli PA, the court’s findings fail to address a number of key factual issues concerning the role of several Tonolli Canada officers in the management of Tonolli PA. The dearth of findings on these issues leaves us with important unanswered questions such that we cannot affirm the conclusion that Tonolli Canada was not an operator of Tonolli PA without further findings. Hence we will remand to the district court for additional proceedings.

The following basic facts were adduced at trial. From 1972 until 1976, Tonolli Canada was the parent and sole shareholder of To-nolli PA. In 1976, Tonolli Canada divested its Tonolli PA stock, selling it for value to IFIM, a company which also became the parent corporation to Tonolli Canada. To-nolli PA did not begin operations until September, 1975, which was only shortly before it was sold to IFIM. After Tonolli Canada sold its Tonolli PA stock, Tonolli PA and Tonolli Canada shared the same president, Elvio Del Sorbo, and the same chief financial officer, Vincent Bailini. From 1984 to 1985, the American Bank & Trust Company of Pennsylvania, a creditor of Tonolli PA, exercised strict, if not total, control over Tonolli PA’s operations.

In support of its conclusion that the two corporations were largely self-supporting and *1223self-sufficient entities during the period that Tonolli PA was operational, the district court made a number of subsidiary findings about the relationship between the two companies which support this conclusion and are supported by the record. For example, although Tonolli Canada had guaranteed To-nolli PA’s financial liabilities when it was the latter’s parent corporation, Tonolli Canada conditioned its sale of Tonolli PA stock to IFIM on the cancellation of these guarantees.14 The district court also found that to the extent that Tonolli Canada had advanced money to Tonolli PA during its start-up period, these advances were all repaid by Tonolli PA shortly after it began operations in 1976. It was also established that each corporation’s lead smelting process was fully operational without support from the other. In addition, each corporation owned its own equipment and procured its own supplies and raw materials. Similarly, each corporation had its own customers, sales staff, legal staff, and engineering consultants.

The district court found that the two companies were kept separate in numerous other respects: they maintained separate corporate minutes; they kept their funds and assets separate; the two companies were separately audited, producing independent financial statements. Each company paid its own bills and conversely neither accepted payment for the other’s products and services provided to third parties. There was no overlap among any non-officer employees, and all facets of the companies’ personnel policies were separate. All of these findings are supported by the record.

The district court also found that all financial transactions between the two companies were conducted on an arm’s-length basis, including, most importantly, the annual management contracts between the two companies. The Authority has argued that the management contracts are actually strong evidence of the operational and financial unity of the two companies. However, the trial testimony established that these annual contracts — in which Tonolli PA paid Tonolli Canada for services it received — were primarily to compensate Tonolli Canada for basic services it provided during the course of a year, i.e., bookkeeping work and computer consulting. There is no indication in the record that Tonolli PA’s payments pursuant to these contracts amounted to anything but the market value of the services it received. In addition, there was no other evidence that the two operated on anything but an arm’s-length basis; there was, for example, no evidence that Tonolli PA was undercapitalized or that Tonolli Canada siphoned off its assets or otherwise used Tonolli PA merely as a source of cash.15 The record, therefore, contains ample evidence supporting the district court’s conclusion as to the separate nature of the two companies.16

However, there are several potentially significant facts that the district court’s findings do not address and which we find disquieting. The two companies shared common officers during the period in question: it is uncontroverted that Del Sorbo served as president and Bailini as chief financial officer of both Tonolli PA and Tonolli Canada. On one hand, the fact that the same people served as the president and chief financial officer for the two corporations is not, without more, enough to conclude that one corporation should be deemed the operator of the other. Because a corporate officer may be a figurehead, there must be evidence that the officer actually exerted control over both corporations. On the other hand, the existence of common high-level officers is troubling and raises serious .questions about the independence of the two companies.

Despite the importance of this issue, the district court failed to make any specific findings about what role Bailini and Del Sorbo played in the management of Tonolli PA. This omission is particularly problematic in *1224light of the fact that in 1984 Bailini signed Tonolli PA’s consent order with the Pennsylvania Department of Environmental Regulation (D.E.R.), which raises questions about his involvement in Tonolli PA’s environmental policies.17 It is further disquieting in light of a document prepared by Del Sorbo containing job descriptions and describing his responsibilities as president of Tonolli PA and Tonolli Canada as well as the responsibilities of several vice-presidents. This document, which stated an effective date of January, 1979, described the two corporations operating as one entity, with the officers of both corporations reporting to the shared president, Del Sorbo. According to this document, the president served in more than a symbolic capacity, exerting final decision-making authority over all facets of the two companies’ operations and management.

Despite the substantial questions raised by this document, the district court made no mention of it in its findings. While it may be that the district court credited Bailini’s testimony that this document was never put into effect,18 we simply do not know. Given the potential import of this document, the district court erred by failing to provide an explanation of its meaning and effect on the operator liability issue.

Although the district court failed to make findings about the respective roles of Bailini and Del Sorbo in the management of Tonolli PA, it did make several findings regarding Sergio Legati. Legati was the vice-president of manufacturing of Tonolli Canada and served as Tonolli PA’s plant manager during 1975-1976 (the start-up period) and again in 1984-85. Legati testified that at other times he intermittently worked on behalf of the Tonolli facility.19 Regarding Legati’s two stints as plant manager for the Tonolli facility, the district court found that, “[although Legati remained an employee of Tonolli Canada[,] .... his role was that of an individual employee temporarily on loan.” Regarding Legati’s part-time work for Tonolli PA, the district court found that Legati worked for the company only as a consultant.

Notwithstanding these findings about Le-gati, the district court’s findings leave critical unanswered questions about Legati’s role. More specifically, the district court failed to make any findings regarding Legati’s role, if any, with respect to Tonolli PA’s release of hazardous substances. Along with Bailini, Legati signed Tonolli PA’s consent order with the D.E.R., raising questions about his role in environmental decisions at the Tonolli site. In addition, although the district court found that there were releases of hazardous substances into the soil at the Tonolli facility, it is unclear from both the record and the court’s findings when the releases occurred. We thus cannot tell whether these releases occurred during the period when Legati served as a full-time plant manager for To-nolli PA. We similarly cannot tell whether they occurred when the American Bank had control over Tonolli PA.

In sum, although the district court made a number of subsidiary findings supporting its conclusion that Tonolli Canada did not exert sufficient control over Tonolli PA to be deemed an operator, its findings do not address a number of critical issues about the roles of several Tonolli Canada officers. We thus remand for the entry of more detailed findings on these issues.

4. Should Tonolli Canada Be Deemed An Owner?

It is well-established that under CERCLA a corporation may be held liable as *1225the owner of another corporation when the attendant circumstances warrant piercing the corporate veil. See, e.g., Joslyn Mfg. Co., 893 F.2d at 83; John S. Boyd Co., 992 F.2d at 408; United States v. Mottolo, 695 F.Supp. 615 (D.N.H.1988). In addition, given the federal interest in uniformity in the application of CERCLA, it is federal common law, and not state law, which governs when corporate veil-piercing is justified under CERCLA. See United States v. Kimbell Foods, Inc., 440 U.S. 715, 99 S.Ct. 1448, 59 L.Ed.2d 711 (1979); see also In re Acushnet River & New Bedford Harbor Proceedings re Alleged PCB Pollution, 675 F.Supp. 22, 30-31 (D.Mass. 1987) (applying federal common law to owner/operator liability under CERCLA). See generally Evelyn F. Heidelberg, Comment, Parent Corporation Liability Under CERC-LA: Toward a Uniform Federal Rule of Decision, 22 Pac.L.J. 854 (1991).

The Authority argues that the district court failed to recognize that operator and owner liability are predicated on different inquiries. It submits that the court therefore did not apply a separate standard to determine whether Tonolli Canada should be held liable as an owner. We disagree. We cannot dispute that the district court’s discussion of the owner liability issue is somewhat vague and that at one point it misspoke by referring to the owner liability issue when it apparently meant the operator liability issue. However, based on our reading of the district court’s findings of fact and conclusions of law, we conclude that the district court did in fact recognize that separate standards govern the imposition of owner and operator liability, applied the appropriate standard to determine whether Tonolli Canada should be deemed an owner, and correctly concluded that it should not.

It is undisputed that Tonolli Canada sold all of its stock in Tonolli PA to IFIM for value in 1976, shortly after the Tonolli PA facility commenced operations. Therefore, for the bulk of the relevant period — the period during which Tonolli PA was operational — Tonolli Canada was Tonolli PA’s sister corporation and no longer its parent. While that fact is inconsequential with respect to the imposition of operator liability, it is generally relevant with respect to owner liability. Put simply, while Congress has provided little guidance in CERCLA as to the appropriate-standard governing owner liability, having defined an “owner” circuitously to be any person owning a facility, 42 U.S.C. § 9601(20)(A)(ii), it is nonetheless clear that owner liability can ordinarily only attach if the defendant meets the common definition of that term and is at least a partial owner of the corporation responsible for the substantive CERCLA offenses. Thus, in contrast to operator liability, corporate ownership is generally a pre-requisite for this status to apply, and Tonolli Canada was not Tonolli PA’s parent corporation for the bulk of the period in question here.

In addition, as we discussed above with respect to the operator liability issue, see supra pages 1222-23, the record establishes that corporate formalities were adhered to, that the two corporations entered transactions on an arm’s length basis, and that Tonolli PA was not undercapitalized. Thus, there is no indication that the circumstances warranted piercing the corporate veil. We will therefore uphold the district court’s conclusion that owner liability should not be imposed.

D. Necessity of Expenses and Consistency with the NCP

In its response to the Authority’s motion for reconsideration, the district court stated that the Authority had failed to provide any evidence that the costs it incurred for the AGES study were necessary and consistent with the NCP, two elements of a prima facie ease under CERCLA. See supra page 1219. However, in a pre-trial order responding to a motion in limine by Tonolli Canada, the district court bifurcated the trial into liability and damages phases and ordered all evidence that the Authority’s expenses were necessary and consistent with the NCP to be reserved for the damages phase. Given the district court’s conclusions that Tonolli Canada was not liable on either count, the district court, of course, never reached the damages phase.

We accept the Authority’s contention that its failure to introduce evidence that its monitoring and evaluation costs were both neces*1226sary and consistent with the NCP was due to its compliance with the district court’s bifurcation order. Under these circumstances, the Authority’s failure to present evidence regarding necessity and consistency with the NCP is not dispositive. On remand, should the district court reach the issue of the necessity of the Authority’s expenses and then-conformity with the NCP, it should give tlje Authority opportunity to present relevant evidence.20

V. IFIM’S LIABILITY

Finally, we turn to the district court’s decision to enter judgment in favor of IFIM on the Authority’s claim for the cost of an alternative water supply and/or treatment of its current supply, and its claim for monitoring and evaluation costs. The Authority argues that the district court erred in entering judgment in favor of IFIM since IFIM never answered the Authority’s complaint, and, under Fed.R.Civ.P. 8(d), when a party fails to respond to a complaint, it is deemed to have admitted all the allegations in the complaint. Although Tonolli Canada does not represent IFIM, it points out that the Authority never moved for the entry of a default judgment, as required by Fed.R.Civ.P. 55(b)(2). The district court provided no explanation for its decision to grant judgment in favor of IFIM on either count.

Despite the absence of an explanation for the district court’s decision, we will affirm the judgment in favor of IFIM on the Authority’s claim for the costs of securing a new water supply and/or continuously treating its existing water supply because the rule requiring consistency in judgments supports this portion of the judgment. See Frow v. De La Vega, 82 U.S. (15 Wall.) 552, 21 L.Ed. 60 (1872). See generally 6 James W. Moore, Walter J. Taggart & Jeremy C. Wicker, Moore’s Federal Practice ¶ 55.06 (2d ed. 1993). The district court found that the Authority’s wells are not threatened by contamination from the Tonolli site due to the hy-drogeological separation of the Authority’s wells and the Tonolli site. This finding, of course, applies as fully to IFIM as to Tonolli Canada and means that IFIM cannot be held hable for contamination that will not occur. We will thus affirm the district court’s judgment on this claim.

However, the rule against inconsistent judgments does not support the judgment in favor of IFIM on the claim for monitoring and evaluation costs because we are vacating the district court’s judgment on the monitoring and response costs claim with respect to Tonolli PA. This rule is further inapplicable to this claim, at least with respect to the operator liability issue, because a conclusion about a subsidiary corporation’s control over a sister company may have no bearing on the parent corporation’s control over that company. Given the lack of evidence at trial either way regarding IFIM’s liability, and the district court’s failure to provide the reason for its judgment in favor of IFIM, we will vacate the judgment of the district court in favor of IFIM on the Authority’s claim for monitoring and response costs and will remand to the district court. On remand, the district court should articulate a basis for its judgment in favor of IFIM, and, if the Authority makes a proper motion, it should consider whether the Authority is entitled to a default judgment.

VI. CONCLUSION

For the foregoing reasons, the district court’s order, to the extent that it grants judgment in favor of Tonolli Canada and IFIM on the claim for recovery for the costs of securing an alternative water supply and/or treating the water from its existing supply wells, will be affirmed. With respect to the Authority’s claim against Tonolli Canada and IFIM for monitoring and evaluation costs, the district court’s judgment will be vacated and remanded for further proceedings. Tonolli Canada has filed a cross-appeal challenging the district court’s denial of its motions for sanctions against the Authority. We hold that the district court did not abuse its discretion in denying sanctions, and hence *1227the district court’s judgment on that issue will be affirmed.

PARKER, Circuit Judge.

This is the second appeal in a suit originally instituted to obtain a declaratory judgment with respect to the coverage of a policy of indemnity insurance. Aetna Casualty & Surety Co. v. Yeatts, 4 Cir., 99 F.2d 665. Following our first decision, the defendant Yeatts filed an amended answer alleging that consent judgment had been entered in the suit for damages filed against him in the state court and asking recovery thereof, together with costs, interest and attorney’s fees, against the insurance company, plaintiff in the suit for declaratory judgment. The company denied liability on the ground that the defendant Yeatts was engaged in the performance of a criminal abortion at the time he incurred the liability for which the recovery was had against him, and that such liability was expressly excluded from the coverage of the policy. The question as to whether the defendant Yeatts was engaged in such criminal conduct was submitted to the jury, and from verdict and judgment in his favor the plaintiff brings this appeal.

There was testimony below from which the jury would have been amply justified in finding in favor of the plaintiff insurance company on the issue submitted; but the defendant himself was examined as a witness and, if his testimony is believed, he was guilty of no criminal act. No motion for directed verdict was made by the plaintiff, nor was the sufficiency of the evidence to sustain a finding in favor, of the defendant challenged in any other way before verdict. After verdict, plaintiff moved for judgment non obstante veredicto and also for a new trial, on the ground that the verdict was contrary to the credible evidence in the case; and exceptions directed to denial of these motions constitute the only points presented by the appeal.

Even if a motion for directed verdict had been made by plaintiff, it is clear that same should liave been denied as should, also, any motion ¿or judgment non obstante veredicto based thereon; for it is too well settled to warrant discussion that, on such motion, the evidence must be taken in the light most favorable to the party against whom the directed verdict is asked and that all conflicts must be resolved in his favor. But here there was no motion for directed verdict to serve as a basis for the motion for judgment non obstante veredicto; and such judgment can be entered on the ground of the insufficiency of the evidence only where motion for directed verdict has been duly made. Rules of Civil Procedure 50(b), 28 U.S.C.A. following section 723c; Baten v. Kirby Lumber Corp., 5 Cir., 103 F.2d 272; Baltimore & Carolina Line v. Redman, 295 U.S, 654, 55 S.Ct. 890, 79 L.Ed. 1636; Montgomery Ward & Co. v. Duncan 311 U.S. 243, 61 S. Ct. 189, 85 L.Ed. 147. In addition, it is well settled that, where the sufficiency of the evidence has not been challenged in this or some other appropriate way during trial, we have no power to review its sufficiency on appeal. Pocahontas Coal & Coke Co. v. Cook, 4 Cir., 74 F.2d 878 and cases there cited. As said by Judge Sibley in Baten v. Kirby Lumber Corporation, supra [103 F.2d 274], “Rule of Civil Procedure 50, 28 U.S.C.A. following section 723c, does not do away with but emphasizes the necessity of a motion for a directed verdict to raise the legal question whether the evidence is sufficient.”

The motion to set aside the verdict and grant a new trial was a matter of federal procedure, governed by Rule of Civil Procedure 59 and not subject in any way to the rules of state practice. On such a motion it is the duty of the judge to set aside the verdict and grant a new trial, if he is of opinion that the verdict is against the clear weight of the evidence, or is based upon evidence which is false, or will result in a miscarriage of justice, even though there may be substantial evidence which would prevent the direction of *353a verdict. The exercise of this power is not in derogation of the right of trial by-jury but is one of the historic safeguards of that right. Smith v. Times Pub. Co., 178 Pa. 481, 36 A. 296, 35 L.R.A. 819; Bright v. Eynon 1 Burr. 390; Mellin v. Taylor 3 B.N.C. 109, 132 Eng. Reports 351. The matter was well put by Mr. Justice Mitchell, speaking for the Supreme Court of Pennsylvania in Smith v. Times Publishing Co., supra [178 Pa. 481, 36 A. 298], as follows: “The authority of the common pleas in the control and revision of excessive verdicts through the means of new trials was firmly settled in England before the foundation of this colony, and has always existed here without challenge under any of our constitutions. It is a power to examine the whole case on the law and the evidence, with a view to securing a result, not merely legal, but also not manifestly against justice, — a power exercised in pursuance of a sound judicial discretion, zvithout zvhich the jury system zvould be a capricious and intolerable tyranny, which no people could long endure. This court has had occasion more than once recently to to say that it was a power the courts ought to exercise unflinchingly.” (Italics supplied).

In the same case, Mr. Justice Williams, in a concurring opinion, traces the history of the exercise of this power and sums up his conclusion as follows:

“ ‘Trial by jury’ therefore meant, at the time of Magna Charta, the investigation and decision of an issue of fact between parties litigant by 12 men, sitting as jurors, under the advice and legal direction of a law judge. When the verdict is rendered by the jury, it is to the court of which they are a part. It is recorded upon the minutes of the court, and becomes a part of the record of the trial; but it does not thereby become a judgment of the court, unless the judge is satisfied with it, and specially or by general order or rule so directs. He has a responsibility for the result no less than the jury, for it is his duty to see that right and justice are done, so far as this may be practicable in the particular case. If he is not satisfied with the verdict, it is his duty to set it aside, and grant a new trial before another jury. This was the settled practice in England as early as 1665. Forsyth, Jury Tr. 164. Lord Holt states that the practice of granting new trials, as a means of correcting the mistakes and relieving against the misconduct of juries, was in use much earlier than 1665, but accounts for its exercise not appearing in the books for the reason that, prior to that date, the action of the courts upon motions was not reported.

*****

“As early, therefore, as 1665, the courts at Westminster did precisely what we have done in this case, and for the same reason. The right of trial by jury was not then supposed to give to a successful party the right to insist on an advantage due to the mistake or the willful misconduct of the jury, no matter how grossly unjust and oppressive the result might be; but the supervisory control of the court in banc, sitting as a court of review, was promptly exercised to relieve against the miscarriage of justice. The exercise of this power was then thought to be in aid of trial by jury. Lord Mansfield, in Bright v. Eynon, 1 Burrows, 390, described the effect of thus granting a new trial as ‘no more than having the cause more deliberately considered by another jury, when there is reasonable doubt, or perhaps a certainty, that justice has not been done.’ The function of the jury was well defined by Chief Justice Holt in Ash v. Ash, Holt, 701, nearly 100 years before the Declaration of Independence: ‘The jury are to try the cause with the assistance of the judge.’ They are not, and have never been, independent of the court of which they are a part, but their verdicts must meet the approval, or at least they must not offend the sense of justice, of the presiding judge, who, as the late Justice Grier, of the supreme court of the United States, was fond of saying, was by virtue of his position ‘the thirteenth juror.’ ”

In 1757, Lord Mansfield in Bright v. Eynon, supra, had this to say with respect to the exercise of the power:

“Trials by jury in civil causes, could not subsist now without a power, somewhere, to grant new trials. * * * There are numberless causes of false verdicts, zvith-out corruption or bad intention of the jurors. They may have heard too much of the matter before the trial; and imbibed prejudices without knowing it. The cause may be intricate: the examination may be so long as to distract and confound their attention. Most general verdicts include legal consequences as well as propositions of fact: in drawing these consequences the jury may mistake, and infer *354directly contrary to law. The parties may be surprised by a case falsely made at the trial, which they had no reason to expect, and therefore could not come prepared to answer. If unjust verdicts obtained under these and a thousand like circumstances, were to be conclusive for ever, the determination of civil property, in this method of trial, would be very precarious and unsatisfactory. It is absolutely necessary to justice, that there should, upon many occasions, be opportunities of reconsidering the cause by a new trial.”

In Mellin v. Taylor, supra, Chief Justice Tindal said: “I cannot conceive how the benefit of trial by jury can be in any way impaired by a cautious and prudent application of the corrective which is now applied for: on the contrary, I think that, without some power of this nature residing in the breast of the Court, the trial by jury would, in particular cases, be productive of injustice, and the institution itself would suffer in the opinion of the public.”

To the federal trial judge, the law gives ample power to see that justice is done in causes pending before him; and the responsibility attendant upon such power is his in full measure. While according due respect to the findings of the jury, he should not hesitate to set aside their verdict and grant a new trial in any case where the ends of justice so require.

The distinction between the rules to be followed in granting a new trial and directing a verdict were stated by us with some care in Garrison v. United States, 4 Cir., 62 F.2d 41, 42, from which we quoted with approval in the later case of Roedegir v. Phillips, 4 Cir. 85 F.2d 995, 996, as follows : “Where there is substantial evidence in support of plaintiff’s case, the judge may not direct a verdict against him, even though he may not believe his evidence or may think that the weight of the evidence is on the other side; for, under the constitutional guaranty of trial by jury, it is for the jury to weigh the evidence and pass upon its credibility. He may, however, set aside a verdict supported by substantial evidence where in his opinion it is contrary to the clear weight of the evidence, or is based upon evidence which is false; for, even though the evidence be sufficient to preclude the direction of a verdict, it is still his duty to exercise his power over the proceedings before him to prevent a miscarriage of justice. See Felton v. Spiro [6 Cir.], 78 F. 576. Verdict can be directed only where there is no substantial evidence to support recovery by the party against whom it is directed or where the evidence is all against him or so overwhelmingly so as to leave no room to doubt what the fact is. Gunning v. Cooley, 281 U.S. 90, 50 S.Ct. 231, 74 L.Ed. 720. Verdict may be set aside and new trial granted, when the verdict is contrary 'to the clear weight of the evidence, or whenever in the exercise of a sound discretion the trial judge thinks this action necessary to prevent a miscarriage of justice.”

It is equally well settled, however, that the granting or refusing of a new trial is a matter resting in the sound discretion of the trial judge, and that his action thereon is not reviewable upon appeal, save in the most exceptional circumstances. Montgomery Ward & Co. v. Duncan, supra, 311 U.S. 243, 61 S.Ct. 189, 85 L.Ed. 147; Fairmont Glass Works v. Cub Fork Coal Co., 287 U.S. 474, 53 S.Ct. 252, 77 L.Ed. 439; Barnes v. South Carolina Public Service Authority, 4 Cir., 120 F.2d 439; Aetna Ins. Co. v. Norris Bros., 4 Cir., 109 F.2d 172; Southern Fruit Distributors v. Fulmer, 4 Cir., 107 F.2d 456; Pocahontas Coal & Coke Co. v. Cook, 4 Cir., 74 F.2d 878; Upton v. Harrison, 4 Cir., 68 F.2d 232; Niagara Fire Ins. Co. of New York v. Raleigh Hardware Co., 4 Cir., 62 F.2d 705. The rule and the reason therefor is thus stated by Mr. Justice Brandéis in Fairmont Glass Works v. Cub Fork Coal Co., supra [287 U.S. 474, 53 S.Ct. 254, 77 L.Ed. 439]: “The rule that this Court will not review the action of a federal trial court in granting or denying a motion for a new trial for error of fact has been settled by a long and unbroken line of decisions; and has been frequently applied where the ground of the motion was that the damages awarded by the jury were excessive or were inadequate. The rule precludes likewise a review of such action by a Circuit Court of Appeals. Its early formulation by this Court was influenced by the mandate of the Judiciary Act of 1789, which provided in section 22 that there should be ‘no reversal in either (circuit or Supreme) court on such writ of error * * * for any error in fact.’ Sometimes the rule has been rested on that part of the Seventh Amendment which *355provides that ‘no fact tried by a jury, shall be otherwise re-examined in any court of the United States than according to the rules of the common law’. More frequently the reason given for the denial of review is that the granting or refusing of a motion for a new trial is a matter within the discretion of the trial court.”

While an examination of the record has led us to the pconclusion that the trial judge might very properly have granted the motion for new trial, we cannot say that his denial of the motion amounted to an abuse of discretion on his part or that there are present any of the special circumstances which would subject his action to review by this court. The judgment appealed from will accordingly be affirmed.

Affirmed.

The opinion of the court was delivered by

Jacobs, J.

The plaintiff suffered serious injuries in an automobile accident and, after trial, received a jury verdict in the sum of $3,000. He applied for a new trial because of the inadequacy of the verdict but his application was denied when the defendants consented that the damages awarded to the plaintiff be increased to the sum of $7,500. The plaintiff appealed and we thereafter certified on our own motion.

On September 17, 1953 motorcycle officer Petras was on traffic duty at the intersection of Bunn’s Lane and Amboy *68Avenue in the Township of Woodbridge. He halted north- and south-bound traffic along Amboy Avenue to enable the crossing of school children. The plaintiffs car was the third in line traveling south along Amboy Avenue and his car came to a full stop as did the two cars ahead of him. He was then struck in the rear by a truck owned by the partnership defendant and driven by the individual defendant. According to the testimony of both the plaintiff and the motorcycle officer the individual defendant explained at the scene of the accident that he thought his foot had “slipped off the brake.” At the trial he denied having made such statement but did admit that he ran into the rear of the plaintiff’s car and that the stoplights on the plaintiff’s car were in proper working order. His story was that after the plaintiff’s car had been brought to a standstill, it started moving again and was then brought to a very sudden stop after having traveled about 12 feet. When the jury returned its unanimous verdict its foreman stated that it had found “negligence on the part of the truck driver.” During the application for new trial the lower court expressed the opinion that “liability was established beyond peradventure of a doubt,” and we entertain the same view.

The plaintiff testified that when his car was struck he “was jerked back and forth” and received “a terriffic bang” on his head; his ear went forward striking the car ahead which in turn struck the first car in line. Although he had received a severe impact he thought he would “be all right” and started to drive home. On the way he “began to get pains,” stopped his car, and was ultimately driven home by a State Trooper. He called Dr. Oopleman, who treated him during the next six weeks. Dr. Copieman testified that his examination showed that the plaintiff was suffering from injury to his neck and back which he diagnosed as “a whip lash injury, the head had been snapped back by an impact.” He treated him originally with “sedatives and drugs for his pain * * * took x-rays of his neck and back, gave him diathermy treatments, and finally had to recommend that he wear a brace for his neck.” *69During this time the plaintiff, though he wore the recommended brace night and day, complained of much pain, and seeing little improvement Dr. Copieman recommended that the plaintiff consult Dr. Hoffman, an orthopedic physician of New Brunswick.

On the advice of Dr. Hoffman the plaintiff entered the Middlesex General Hospital on November 1, 1953 and remained there for two weeks. During that time he was placed in traction, which failed, however, to relieve his intense pain. Dr. Hoffman suspected that the plaintiff was suffering from a ruptured disc and he consulted Dr. Scheuerman, a neurological surgeon of Trenton. Dr. Scheuerman examined the plaintiff on November 17, 1953, made a diagnosis of probable ruptured disc, and recommended that he return to the hospital for further study. The plaintiff returned to the hospital on November 23, 1953 and a myelogram was performed; it confirmed that the plaintiff had a ruptured disc, and a hemilaminectomy was performed by Dr. Scheuerman with Dr. Hoffman assisting. The plaintiff was discharged from the hospital on December 10, 1953; he remained at home until February 15, 1954 and then returned to his employment, but only on a part-time basis. On July 20, 1954 he returned to the hospital where Dr. Scheuerman removed oil which had been inserted in the spinal canal during the myelogram. He did not resume full-time work until September 1954.

Dr. Scheuerman testified that he administered postoperative treatment to the plaintiff, who has continued to have some pain and is “not able to do all of the usual duties that he had previously.” Dr. Hoffman testified that the operation on the plaintiff left a residual which he described as follows:

“Well, he has had a great deal of pain in the back. At one time he had a listing of the pelvis, in that the iliac crests were not level. And at that time he had a thickened sole prescribed and heel, to bring it up to normal. And he has no reflexes on the left side, no quadriceps extensor reflexes, or patellar reflexes; and he has atrophy of the calf muscles, compared with the opposite side, it is a little over a half an inch in circumference difference.”

*70The plaintiff testified that he still is unable to perform his heavier duties and experiences back and leg pains for which he takes prescribed narcotics, is unable to sleep without sedation, and is unable to sit at one place for any substantial length of time. Both Dr. Scheuerman and Dr. Hoffman testified that there was a aausal relation between the plaintiff’s accident on September 17, 1953 and the hemilaminectomy which was performed thereafter. No medical testimony whatever to the contrary was introduced by the defendants, although they do urge that the plaintiff’s injuries were attributable, at least in part, to an earlier accident which he suffered on February 3, 1950.

The 1950 accident resulted in a law action by the plaintiff which was later discontinued. In answers to interrogatories in that action the plaintiff stated that he was “partially prevented from attending his work between February 20th and February 27th, 1950”; that his injuries were “concussion; lumbo-sacral back sprain; vertigo; headaches; tinnitus or ringing of both ears and slight loss of hearing in both ears”; that he “will claim permanent injury to his back and loss of hearing and headaches”; and that his last medical treatments were in May and June 1950. However, the record indicates that the plaintiff actually suffered no really pertinent aftermaths of the 1950 accident. He testified (and there is nothing before us to suggest otherwise) that after February 27, 1950 and prior to his accident of September 17, 1953 he never lost a day’s work “outside of having a cold or something like that,” and that during that period his health was good and he engaged in sports and heavy work in normal fashion. The defendants suggest that prior to the 1953 accident the plaintiff had a “chronic back condition,” which they relate to the later operation for a ruptured disc, and they refer specifically to a hospital record entry by Dr. Hoffman; but Dr. Hoffman made the entry on November 1, 1953 and explained that he was referring to the plaintiff’s condition after the 1953 accident; in his own language: “I didn’t say he had a chronic back prior to the accident. That was only after the accident.”

*71The plaintiff’s actual expenditures to doctors and nurses and for drugs and hospitalization exceeded $2,200. And although he received most of his normal earnings despite his temporary incapacity, there was a loss of wages approximating $620. While the jury’s verdict of $3,000 just about took care of the plaintiff’s actual monetary losses, it awarded substantially nothing for his suffering and permanent injuries. Its gross inadequacy was recognized by the trial judge who pointed out that “there was no dispute but that the plaintiff suffered excruciating pain, and was rendered totally helpless for a considerable period of time.” On June 28, 1956 the trial judge wrote to the parties advising that unless the defendants filed a consent in writing that the verdict be increased from $3,000 to $7,500, “then the verdict heretofore rendered will be set aside and a new trial granted limited to damages only.” The consent was filed by the defendants and on June 30, 1956 a formal order was entered dismissing the plaintiff’s motion for a new trial. Though it was unnecessary, the plaintiff obtained leave to appeal from the Appellate Division. See R. R. 2:2-1; R. R. 4:61; cf. State v. Richter, 21 N. J. 421 (1956), certiorari denied 351 U. S. 975, 76 S. Ct. 1039, 100 L. Fd. 1492 (1956); State v. Haines, 20 N. J. 438 (1956); Palm Beach Mercantile Co. v. Ivers, 2 N. J. Super. 5 (App. Div. 1949); 6 Moore’s Federal Practice 3891 (2d ed. 1953).

The first point which he urges in support of his appeal is that once the trial court had concluded that the damages awarded by the verdict were inadquate it had no legal power whatever to condition the grant of a new trial upon the defendants’ failure to consent to a prescribed increase in the verdict. But see Gaffney v. Illingsworth, 90 N. J. L. 490, 492 (E. & A. 1917); Fsposito v. Lazar, 2 N. J. 257, 259 (1949); Elvin v. Public Service Coordinated Transport, 4 N. J. Super. 491, 494 (App. Div. 1949); 1 Bradner, New Jersey Law Practice § 389 (McC. Marsh 1940); Harris, Pleading and Practice in New Jersey § 664 (rev. ed. 1939); Sheen, New Jersey Law Practice 458 (2d ed. 1931). Much has appeared in the law reviews in support of the practices *72of remittitur and. additur as enlightened aids in securing substantial justice between the parties without the burdensome costs, delays and harassments of new trials. See Carlin, “Remittiturs and Additurs ,” 49 W. Va. L. Q. 1 (1942); Note, “Correction of Damage Verdicts by Remittitur and Additur,” 44 Yale L. J. 318 (1934); Note, “Additur in California,” 40 Cal. L. Rev. 276 (1952); Note, “Additur and Remittitur,” 26 Va. L. Rev. 836 (1940). Cf. Millar, “Notabilia of American Civil Procedure,” 50 Harv. L. Rev. 1017, 1052 (1937); Scott, Fundamentals of Procedure in Actions at Law 119-131 (1922). The term remittitur is used to describe an order denying the defendant’s application for new trial on condition that the plaintiff consent to a specified reduction in the jury’s award, whereas the term additur is used to describe an order denying the plaintiff’s application for a new trial on condition that the defendant consent to a specified increase in the jury’s award. While it is now recognized that the two practices are logically and realistically indistinguishable, remittiturs have been recognized almost everywhere, whereas additurs are still outlawed in some, though by no means all, of the states. Compare O’Connor v. Papertsian, 309 N. Y. 465, 131 N. E. 2d 883 (1956), where the New York Court of Appeals unanimously sustained an Appellate Division order which denied a new trial upon the defendant’s consent to increase the $1,000 awarded by the jury to the sum of $2,500, with Dorsey v. Barba, 38 Cal. 2d 350, 240 P. 2d 604 (1952), where the Supreme Court of California (with Justice Traynor dissenting) held that although its courts could properly deny new trials upon consents by plaintiffs to reductions, they could not properly do so upon consents by defendants to increases. See 25 Fordham L. Rev. 150 (1956); 31 N. Y. U. L. Q. 1537 (1956); 40 Cal. L. Rev., supra; 10 Wash. & Lee L. Rev. 46 (1953).

The English precedents prior to the American Devolution are somewhat obscure and they are discussed in the majority and minority opinions in Dimick v. Schiedt, 293 U. S. 474, 55 S. Ct. 296, 302, 79 L. Ed. 603 (1935). There Justice *73Sutherland, speaking for a majority of five (with Justice Stone, joined by Chief Justice Hughes and Justices Brandéis and Cardozo, dissenting) held that although remittitur is permissible, in the federal courts, additur is prohibited by the force of the provision in the Seventh Amendment that “the right to trial by jury shall be preserved, and that 'no fact tried by a jury shall be otherwise re-examined by any court of the United States, than according to the rules of the common law.’” In Belt v. Lawes (1884), 12 Q. B. 356, the court sustained the denial of a new trial upon the plaintiff’s consent to accept a lesser amount than that awarded by the jury; on appeal, Brett, M. R. not only approved the practice followed below but suggested that the court would also have power “to say that the damages given are too small, but that if the defendant will agree to their being increased to such a sum as may be stated, a new trial shall be refused.” Cf. Armytage v. Haley (1843), 4 Q. B. 917, 114 Eng. Rep. 1143. In the later case of Watt v. Watt (1905), A. C. 115 the court took an opposite position and rejected the view that a court could condition a denial of a new trial on the plaintiff’s acceptance of a reduced verdict. Lord Davey acknowledged that a contrary practice had grown up and that it generally served substantial justice; but he considered that there was a lack of common law power and referred to various judicial dicta to the effect that a jury’s award of damages could not be reduced “without the consent of both parties.” However, Justice Sutherland in the Dimich case did not follow the result in the Watt case and declined to upset the remittitur practice, first approved by Justice Story in Blunt v. Little, 3 Fed. Cas. No. 1,578 ( C. C. Mass. 1822), and since reaffirmed in many federal decisions. See Arkansas Valley Land & Cattle Co. v. Mann, 130 U. S. 69, 9 S. Ct. 458, 32 L. Ed. 854 (1889), and the other cases cited in Moore, supra 3739.

In his dissenting opinion in the Dimick case, Justice Stone pointed out that the Seventh Amendment was concerned with substance rather than form and that the *74Supreme Court had often declined to construe it as perpetuating in changeless form the minutiae of trial practice as it existed in the English courts in 1791; he referred to the many jury procedures unknown to the common law but now well established in federal practice; he considered wholly impersuasive the suggested differentiation between the settled remiUUur practice which the majority continued and the additur practice which it rejected; and he concluded with the following remarks (293 U. S., at page 496, 55 S. Ct., at page 305, 79 L. Ed., at page 616) :

“Appellate federal courts, although without common law precedent, have not hesitated to resort to the remittitur where, by its use, the necessity of a new trial could justly be avoided. Bank of Kentucky v. Ashley, 2 Pet. 327, 329, 7 L. Ed. 440, [441]; Phillips & C. Constr. Co. v. Seymour, 91 U. S. 646, 656, 23 L. Ed. 341, [345]; Hopkins v. Orr, 124 U. S. 510, 514, 8 S. Ct. 590, 31 L. Ed. 523, [525]; Washington & G. R. Co. v. Harmon’s Adm’r (Washington & G. R. Co. v. Tobriner), 147 U. S. 571, 590, 13 S. Ct. 557, 37 L. Ed. 284, [291]; Hansen v. Boyd, 161 U. S. 397, 411, 412, 16 S. Ct. 571, 40 L. Ed. 746, [751]. The trial judge who denies a motion for a new trial, because the plaintiff has consented to reduce, or a defendant has consented to increase, the amount of the recovery, does no more than when, sitting in equity, he withholds relief upon the compliance with a condition, the performance of which will do substantial justice. See Harrisonville v. W. S. Dickey Clay Mfg. Co., 289 U. S. 334, 338, 53 S. Ct. 602, 77 L. Ed. 1208, [1211],

To me it seems an indefensible anachronism for the law to reject the like principle of decision, in reviewing on appeal denials of motions for new trial, where the plaintiff has consented to decrease the judgment or the defendant has consented to increase it by the proper amount, or to apply it in the one case and reject it in the other. It is difficult to see upon what principle the denial of a motion for a new trial, which for centuries has been regarded as so much a matter of discretion that it is not disturbed when its only support may be a bad or inadequate reason, may nevertheless be set aside on appeal when it is supported by a good one: That the defendant has bound himself to pay an increased amount of damages which the court judicially knows is within the limits of a proper verdict.”

The majority opinion in Dimick has been the subject of much criticism and it is doubtful whether the Supreme Court would still subscribe to it; in any event, the Seventh *75Amendment differs somewhat from onr constitutional provision and has no application to proceedings in our state courts. Walker v. Sauvinet, 92 U. S. 90, 23 L. Ed. 678 (1876); Pearson v. Yewdall, 95 U. S. 294, 24 L. Ed. 436 (1877). Cf. Maxwell v. Dow, 176 U. S. 581, 20 S. Ct. 448, 44 L. Ed. 597 (1900); Fay v. People of State of New York, 332 U. S. 261, 288, 67 S. Ct. 1613, 91 L. Ed. 2043, 2060 (1947). We must look primarily to our own history and precedents in ascertaining whether the highly desirable practices of remittitur and additur may be adhered to in our State without infringement of Art. I, par. 9 of the 1947 Constitution which provides as follows:

“The right of trial by jury shall remain inviolate; but the Legislature may authorize the trial of civil causes by a jury of six persons when the matter in dispute does not exceed fifty dollars. The Legislature may provide that in any civil cause a verdict may be rendered by not less than five-sixths of the jury. The Legislature may authorize the trial of the issue of mental incompetency without a jury.”

The Constitution of 1776 had provided (Art. XXII) that “the inestimable right of trial by jury shall remain confirmed, as a part of the law of this colony, without repeal, forever”; and the Constitution of 1844 had provided (Art. I, par. 7) that “the right of trial by jury shall remain inviolate; but the legislature may authorize the trial of civil suits, when the matter in dispute does not exceed fifty dollars, by a jury of six men.” But our high courts have consistently recognized that the treasured constitutional right of trial by jury relates to substance rather than form and does not preclude efficient procedural devices which, though perhaps not strictly part of the English common law, are nevertheless wholly consistent with the fundamental right of the parties to have the facts determined by a fair and impartial jury acting under appropriate judicial guidance and control. In Clayton v. Clark, 55 N. J. L. 539, 540 (Sup. Ct. 1893), the court noted that the Constitution provides that the right to trial by jury “shall remain inviolate, not that it *76shall be unalterable,” and later decisions have embodied the same expression. See Slate v. DeLorenzo, 81 N. J. L. 613, 616 (E. & A. 1911); Sexton v. Newark Dist. Telegraph Co., 84 N. J. L. 85, 101 (Sup. Ct. 1913), affirmed 86 N. J. L. 701 (E. & A. 1914); Robinson v. Payne, 99 N. J. L. 135, 141 (E. & A. 1923). Similarly, in Humphrey v. Eakeley, 72 N. J. L. 424, 426 (Sup. Ct. 1905), affirmed 74 N. J. L. 599 (E. & A. 1907), the court stressed that the constitutional language imports freedom from harm or substantial impairment but not “immunity from all regulation.” See State v. Maier, 13 N. J. 235, 276 (1953).

The remittitur practice has been recognized in New Jersey since early days. New Jersey Flax Cotton Wool Co. v. Mills, 26 N. J. L. 60, 63 (Sup. Ct. 1856); Rafferly v. Bank of Jersey City, 33 N. J. L. 368, 372 (Sup. Ct. 1869); Rafferty v. Erie R. Co., 66 N. J. L. 444, 450 (Sup. Ct. 1901); Harris, supra. Not until 1916 was it questioned, but the Court of Errors and Appeals found little difficulty in sustaining it. Heinz v. Delaware, L. & W. R. Co., 90 N. J. L. 198 (E. & A. 1916). Justice Trenchard, speaking for a unanimous court, pointed out that in England the power had been denied in Watt v. Wait, supra (which had in turn overruled Belt v. Lawes, supra), but that in our State it had frequently been invoked “to do substantial justice and save the expense of a new trial” and that it was “in no sense an impairment of the constitutional right of trial by jury.” During the following year, the Court of Errors and Appeals had occasion to deal with a negligence case in which the practice of additur had been invoked. Gaffney v. Illingsworth, supra. The jury had returned a verdict of $190.25 and Judge Dungan thereafter announced that if the defendant would consent to pay the sum of $480.50 rather than the amount awarded by the jury, he would deny the plaintiff’s application for a new trial; the defendant declined and a new trial limited to damages was awarded. The defendant appealed, contending that the trial court had no authority to set aside a verdict and grant a new trial as to damages alone. Notwithstanding the absence of any such common *77law power (Scott, supra, 113) the Court of Errors and Appeals summarily disposed of the defendant’s contention by reference to the provisions of the Practice Act of 1913 and the implementing court rules, which explicitly provided for new trials limited to damages. See Robinson v. Payne, supra. The defendant also urged that the additur condition imposed by Judge Dungan was beyond his power; in response, Chancellor Walker, speaking for the entire court, had this to say (90 N. J. L., at page 492):

“The power of the court in granting a new trial upon the ground that the damages are excessive, upon terms that a new trial shall be had unless the plaintiff will accept a certain sum named, less than that awarded by a verdict, is too well established to be questioned. It would seem to follow, by parity of reasoning, that when a new trial is granted because the damages are inadequate, the court may impose like terms, that is, terms to the effect that if the defeated party will pay a certain sum, greater than that awarded by the verdict, the rule will be discharged, subject, doubtless, to the power of an appellate court to vacate any such terms when they appear to be an abuse of discretion. No such showing is made on the record before us, and this makes it inappropriate for us to give consideration to the appellant’s other contention, namely, that the verdict, as it stands, is adequate and proper and evinces no prejudice or partiality on the part of the jury. As to whether or not the verdict is adequate and proper is, on application for a new trial, a matter of sound discretion in the trial court, and, in the absence of an abuse of discretion, the appellate court cannot review the trial court’s action. And with the question of damages, apart from such discretion, we have nothing to do.” '

The Gaffney case was widely accepted as upholding additur as well as remittitur in our State. Scott, supra, 128; Carlin, supra, 25; Harris, supra; Bradner, supra. Thus, Dean Harris in his book on Pleading and Practice and Professor Marsh in his revision of Bradner stated unequivocally that the trial court had power to condition its denial of a new trial upon the plaintiffs consent to accept a reduced amount or upon the defendant’s consent to pay an increased amount. The following summary in 1939 by Dean Harris may be said to have represented the general understanding by the bench and bar:

*78“In granting a new trial on the ground that the verdict is excessive, the court in its discretion may give the plaintiff the option either of accepting a specified reduced amount of verdict, or being put to a new trial. Similarly, when the verdict is, in the opinion of the court, inadequate, the court may give the defendant the option either of paying a greater sum than awarded by the verdict or of submitting himself to a new trial. The power to impose such terms is inherent in the court and is regulated by the rules of the Supreme Court. Such power may be exercised in contract actions, as well as in tort actions involving unliquidated damages. The exercise of the power of the court in imposing such terms upon the parties is discretionary, and in the absence of an abuse of discretion, not subject to an appeal. This is one of the constitutional prerogatives of the court, which cannot be interfered with by legislation.” Harris, supra, § 664.

The delegates to our Constitutional Convention of 1947 included many members of the legal profession who sought to furnish our State with a modern judicial structure which would retain benefits of the old while acquiring advantages of the new. Though aware of the high function of the jury system as an instrument of justice, they knew that it had been constitutionally subject to enlightened judicial controls and regulations which did not impair its basic integrity. Thus they were fully familiar with the trial court’s power to withdraw a case from the jury because of the insufficiency of the evidence (Harris, supra, §§ 535, 538), to require that the jury render a special verdict or answer special interrogatories (Harris, supra, § 555), and to grant or deny a total or partial new trial upon terms which might include remittitur or additur (Harris, supra, § 664). At no point during the Constitutional Convention or thereafter was there any suggestion that these preexisting judicial controls and regulations should in anywise be curbed; on the contrary, the significant movement relating to the right to trial by jury was in itself designed to avoid “costly retrials” (1 Record of Proceedings, Const. Conv. of 1947, p. 610) and resulted in the express constitutional provision authorizing the Legislature to provide for five-sixths verdicts in civil cases. Const. 1947, Art. I, par. 9.

Shortly after the adoption of the 1947 Constitution our courts had occasion to deal anew with the practices of *79 remittitur and additur. In Esposito v. Lazar, supra, the jury returned a verdict for plaintiff in the sum of $1,200; the trial court found the damages inadequate and ordered a new trial limited to damages unless the defendant consented to increasing the award to $3,500. The defendant refused and on retrial the jury awarded $3,000. On appeal, this court, in an opinion by Justice Ackerson, approvingly cited Gaffney v. Illingsworth, supra, and expressly recognized that a trial court has discretionary power to deny a new trial upon the plaintiff’s consent to accept a reduced amount ot upon the defendant’s consent to pay a larger amount. See 2 N. J., at page 259. It held, however, that in the case before it the new trial should not have been limited to damages because the original jury verdict appeared to represent a compromise finding on the issue of liability. See Hendrikson v. Koppers Co., Inc., 11 N. J. 600, 608 (1953); Juliano v. Aleles, 114 N. J. L. 510 (Sup. Ct. 1935). Cf. Dahle v. Goodheer, 38 N. J. Super. 210 (App. Div. 1955), certiorari denied 20 N. J. 534 (1956).

In Elvin v. Pubic Service Coordinated Transport, supra, the Appellate Division summarized the pertinent judicial controls which had been exercised in our old practice and have been continued in our new; in the course of his opinion for the court, Judge McGeehan said:

“In New Jersey, the judge in the trial of a negligence action has certain recognized controls over the jury verdict when he deems it inadequate. Under Rule 3:59-l the judge may grant a new trial as to all or part of the issues, upon motion made to him. Under Rule 3:59-4 the judge, of his own initiative, may order a new trial for any reason for which he might have granted a new trial upon motion of a party. Further, the judge, in his discretion, may give the defendant the option of paying a stated increase in the amount of the verdict or of going on to a new trial as to the amount of damages, subject to the power of an appellate court to vacate any such terms when they appear to be an abuse of discretion. Esposito v. Lazar, 2 N. J. 257 (1949), which is a control not permitted in the Federal courts; Dimick v. Schiedt, 293 U. S. 474, 79 L. Ed. 603 [1935], or in the English courts (Watt v. Watt (1905), A. C. 115, 6 B. R. C. 1).”

*80In the light of all of the foregoing, we are satisfied that the practices of remittitur and additur violate none of onr constitutional interdictions and, if fairly invoked, serve the laudable purpose of avoiding a further trial where substantial justice may be attained on the basis of the original trial. See Meszaros v. Gransamer, 23 N. J. 179 (1957). Accordingly, we reject the first point urged by the plaintiff and come now to his meritorious contention that, in any event, the prescribed increase to $7,500 was “grossly inadequate and should be set aside.” notwithstanding earlier doubts (Nelson v. Eastern Air Lines, Inc., 128 N. J. L. 46, 55 (E. & A. 1941)) there is now no question as to the power of our appellate courts to reverse a trial court’s refusal to grant a new trial (whether or not conditioned on remittitur or additur) where it is satisfied that there has been “an abuse of discretion” (Esposito v. Lazar, supra; Elvin v. Public Service Coordinated Transport, supra) or, in the more modern terminology, “ ‘a manifest denial of justice.’ ” See Lindroth v. Christ Hospital, 21 N. J. 588, 596 (1956); Conklin v. Miele’s Motor Transportation, Inc., 43 N. J. Super. 420, 428 (App. Div. 1957). In the instant matter, we believe that the trial judge had a mistaken notion of the evidence which led to his prescribing the scanty sum of $7,500. He stated that the plaintiff was not entitled to a “great sum, because he certainly did have a back condition before this accident occurred”; but the evidence in the record points to the view that whatever “back condition” the plaintiff had as a result of the 1950 accident had cleared up and had no relation to the very severe injuries resulting from the 1953 accident. Under these highly special circumstances, we believe that the trial court’s action should not be permitted to stand and that the interests of justice will best be served by permitting a second jury to pass on the issue of damages. The separable issue of liability was clearly and properly decided against the defendants; under the evidence it could hardly have been determined otherwise and need not be submitted for redetermination. R. R. 4:61-1; Dahle v. Goodheer, supra.

*81Eeversed, with direction for a new trial on the issue of damages.

Heher, J.

(concurring in result). The right of trial by jury secured by Article I, paragraph 9 of the 1947 State Constitution, as under like guaranties of the 1844 Constitution, Article I, paragraph 7, and the 1776 Constitution, Article XXII, “is the right as it existed at common law and remained on July 2, 1776,” not as enlarged by statute, as if “* * * each constitutional provision speaks anew as of the time of the adoption of the instrument of which it is a part * * *.” Town of Montclair v. Stanoyevich, 6 N. J. 479 (1951). See Board of Health of Weehawken Tp. v. New York Central R. Co., 10 N. J. 294 (1952). The right “* * * is not to be impaired or diminished, but is to remain as it existed at .common law, and according to the practice of the courts anterior to the establishment of the fundamental law.” State v. Doty, 32 N. J. L. 403 (Sup. Ct. 1868), Beasley, C. J. See also Howe v. Treasurer of Plainfield, 37 N. J. L. 145 (Sup. Ct. 1874). The jurors “compose the appropriate tribunal for the determination of controverted questions of fact * * *.” Kohl v. State, 59 N. J. L. 445 (E. & A. 1896). And see State v. Knight, 96 N. J. L. 461 (E. & A. 1921). Trial by jury as the means of determining “questions of fact” is of great antiquity, importing a jury of 12 men, impartially selected, whose verdict was required to be by the concurrence of all. Brown v. State of New Jersey, 62 N. J. L. 666 (E. & A. 1899), affirmed 175 U. S. 172, 20 S. Ct. 77, 44 L. Ed. 119 (1899). The constitutional requirement that “the right to a trial by jury shall remain inviolate” guarantees “the opportunity to submit common law rights to a tribunal that shall possess the attributes of the historical jury as it existed at the time of the adoption of the organic law.” Clayton v. Clark, 55 N. J. L. 539 (Sup. Ct. 1893).

And the constitutional right of trial by jury controls the exercise of judicial power at the trial level to set aside a verdict as contrary to the weight of the evidence and for *82appellate relief to the same end; the court “may not merely weigh the evidence where it is fairly susceptible of divergent inferences and substitute its own judgment for that of the jury,” but if the verdict be “so far contrary to the weight of the evidence as to give rise to the inescapable conclusion of mistake, passion, prejudice, or partiality,” it transcends the constitutional province of the jury and is remediable as an excess of power; the court may not set aside a verdict merely because, in its opinion, the jury upon the evidence might well have found otherwise; and this conception of the weight of the evidence applies to civil and criminal cases. Hager v. Weber, 7 N. J. 201 (1951).

As is shown by Justice Sutherland’s analysis of the case history in Dimick v. Schiedt, 293 U. S. 474, 55 S. Ct. 296, 79 L. Ed. 603 (1935), there was no power in the English courts at the time of the adoption of the New Jersey Constitution of 1776 to increase, either absolutely or conditionally, the damages fixed by a jury in a case such as this. The power to increase the award had been exercised on occasion (a) in actions for mayhem, upon view of the party maimed; (b) where damages had been assessed upon a writ of inquiry, and then upon the ground that the justices might themselves have awarded damages without the writ; and (c) in some of the old cases where the amount of the plaintiff’s demand was certain, as, for example, in an action of debt.

In Beardmore v. Carrington, 2 Wils. 244, 95 Eng. Repr. 790, decided in 1764, the holding was that the English courts were without power either to increase or reduce damages in any action for a personal tort, unless in the exceptional cases noted ante. The practice of granting new trials was there termed “modern,” a power courts “anciently never exercised,” although “in some particular cases they corrected the damages from evidence laid before them.” The court continued:

“There is great difference between cases of damages which [may] be certainly seen, and such as are ideal, as between assumpsit, trespass for goods where the sum and value may be measured, and *83actions of imprisonment, malicious prosecution, slander and other personal torts, where the damages are matter of opinion, speculation, ideal; there is also a difference between a principal verdict of a jury, and a writ of inquiry of damages, the latter being only an inquest of office to inform the conscience of the Court, and which they might have assessed themselves without any inquest at all; only in the case of maihem, Courts have in all ages interposed in that single instance only; as to the case of the writ of inquiry in the Year-Book of H.4, we doubt whether what is said by the Court in that case be right, that they would abridge the damages unless the plaintiff would release part thereof, because there is not one case to be found in the Year-Books where ever the Court abridged the damages after a principal verdict, and this is clear down to the time of [Hawkim v. Soiet] Palmer’s Rep. 314, [81 Eng. Repr., 1099] much less have they interposed in increasing damages, except in the case of maihem; * *

And in Mayne’s Treatise on Damages (9th ed.), 571, the first edition of which was published in 1856, it is said that “in cases where the amount of damages was uncertain their assessment was a matter so peculiarly within the province of the jury that the Court should not alter it.” The author continues, p. 580:

“When an excessive verdict is given, it is usual for the judge to suggest to counsel to agree on a sum, to prevent the necessity of a new trial. In the absence of agreement the Court has no power to reduce the damages to a reasonable sum instead of ordering a new trial. It would seem also from what was said in the case in which this was recently decided, that where the damages are too small, the Court cannot with the defendant’s consent increase them, if the plaintiff asks for a new trial.”

In Watt v. Watt (1905), A. C. 115, 6 B. B. C. 1, 2 Ann. Cas. 672, the House of Lords said the idea that the court could with the consent of the plaintiff reduce the amount of the damages probably arose from the fact that in the old cases the courts had “adopted the somewhat unconstitutional proceeding of refusing to give the plaintiff judgment unless he would consent to reduce his claim to what ought to be considered reasonable,” an indirect method implying the need for the plaintiff’s assent; and that since the defendant was not likely to refuse his assent to a proceeding intended for his benefit, the theory of the cases seems to *84have been that the right of the court to interfere with the verdict depended upon the consent of both parties; and the contrary hypothesis here contended for was utterly repudiated as alien to the common law and sound English practice.

The Earl of Halsbury, L. C. there affirmed that the Court of Appeal “has no jurisdiction to fix the amount of damages without the consent of both parties”; he attributed the “confusion” in this regard to the practice upon demurrer or default, where the court may have the sheriff assess the damages, the usual course, or “* * * decide that question for itself — probably because that question is often a question of law, where the damages are fixed by law * * and he noted the “* * * distinction between trial by jury and mere inquisition or inquiry by a jury to assess damages — that, in the latter case the inquisition was only to inform the mind of the court and it was at their discretion whether they would award judgment for the amount found by the jury, where as upon a trial they had no jurisdiction to interfere as to the amount of damages in cases of tort,” citing Reeves’ History of the Common Law, and that the “theory of all the cases seems to me to be that the right of the court to interfere with a jury’s verdict was only to be by the assent of both parties.”

And Lord Robertson declared the contrary view “is on principle indefensible.”

In the later case of Barber & Co. v. Deutsche Bank (1919), A. C. 304, H. L., Lord Phillimore affirmed the true principle to be this:

“Where damages are at large and the Court of Appeal is of opinion that the sum awarded is so unreasonable as to show that the jury has not approached the subject in a proper judicial temper, has admitted considerations which it ought not to have admitted, or rejected or neglected considerations which it ought to have applied, it is the right of the party aggrieved to have a new trial. He is not to be put off by the Court saying that it will form its opinion as to the proper sum to be awarded, and reduce or enlarge the damages accordingly. He is entitled to an assessment by a jury which acts properly. He is not to be put off by a composite de*85cisión, or I might describe it as a resultant of two imperfect forces — an assessment partly made by a jury which has acted improperly and partly by a tribunal which has no power to assess.”

And so, in Dimick v. Schiedt, supra, Justice Sutherland concluded, and with unquestionable authority, that “while there was some practice to the contrary in respect of decreasing damages, the established practice and the rule of the common law, as it existed in England at the time of the adoption of the Constitution, forbade the court to increase the amount of damages awarded by a jury in actions such as that here under consideration.” He observed that “this court in a very special sense is charged with the duty of construing and upholding the Constitution; and in the discharge of that important duty, it ever must be alert to see that a doubtful precedent [involving remittitur] be not extended by mere analogy to a different ease if the result will be to weaken or subvert what it conceives to be a principle of the fundamental law of the land”; and that “the power to conditionally increase the verdict of a jury does not follow as a necessary corollary from the power to conditionally decrease it,” since in the case of a conditional remittitur “a jury. has already awarded a sum in excess of that fixed by the court as a basis for a remittitur, which at least finds some support in the early English practice, while in the second case, no jury has ever passed on the increased amount, and the practice has no precedent according to the rules of the common law.”

The “controlling distinction between the power of the court and that of the jury,” said Justice Sutherland, “is that the former is the power to determine the law and the latter to determine the facts,” and while the remittitur practice in the case of an excessive verdict “is not without plausible support in the view that what remains is included in the verdict along with the unlawful excess, — in the sense that it has been found by the jury, — and that the remittitur has the effect of merely lopping off an excrescence,” yet where an inadequate verdict is increased by the court there is a “bald addition of something which in no sense can be *86said to be included in the verdict,” and if that be done with the consent of the defendant alone, the plaintiff is compelled to forego his “constitutional right to the verdict of a jury and accept 'an assessement partly made by a jury which has acted improperly, and partly by a tribunal which has no power to assess.’ ”

It was there pointed out that while the remittitur practice had acceptance in the federal jurisdiction for more than a century, following Justice Story’s ruling at the circuit in Blunt v. Lillie, Fed. Cas. No. 1,578, 3 Mason 102 (C. C. 1822), no federal court had undertaken to increase a jury award of damages, although there are numerous cases in which a new trial was granted for inadequate damages. And this is equally true of New Jersey, save that in Gaffney v. Illingsworth, 90 N. J. L. 490 (E. & A. 1917), a new trial was ordered unless the defendant would consent to an increase of the jury’s verdict of $190.25 for the plaintiff to $480.50. In Esposito v. Lazar, 2 N. J. 257 (1949), error was found in the award of a new trial limited to damages in that the amount of the verdict indicated a “compromise” on liability.

There can be no doubt that the addiiur practice sanctioned here contravenes the essence of the common-law right of trial by jury at the time of the adoption of the 1776 Constitution, then and ever since a basic right under the law of England; and this is the very substance of our own constitutional guaranty. We are still a common-law State; and the essential principles of the common law are in force except as modified by our own Constitution and statutes enacted in keeping with the Constitution. This, in virtue of an explicit constitutional mandate. Taneian v. Meghrigian, 15 N. J. 267 (1954).

The reasoning of the minority in Dimiclc proceeds on the hypothesis, “long accepted in the federal courts,” that the “exercise of judicial discretion in denying a motion for a new trial, on the ground that the verdict is too small or too large, is not subject to review on writ of error or appeal,” a “special application of the more general rule that an *87appellate court will not re-examine the facts which induced the trial court to grant or deny a new trial,” and the unwilling plaintiff whose inadequate verdict has been increased by the court “has suffered no denial of a right because the court, staying its hand, has left the verdict undisturbed, as it lawfully might have done if the defendant had refused to pay more than the verdict,” and, although the common law had made no rule on the subject in 1791, the court could not “rightly refuse to apply to either the principle of general application that it is competent to exercise a discretionary power to grant or withhold relief in any way which is not unjust,” analogizing the judge’s function, “when sitting in equity,” to withhold “relief upon the compliance with a condition, the performance of which will do substantial justice,” citing Belt v. Lawes, L. R. 12 Q. B. Div. 356 (C. A. 1884), a remittitur case overruled by the House of Lords in Watt v. Watt, cited supra.

But this rationale does not take into account the basic quality of our own constitutional right of trial by jury, after the mode and manner and essentiality of the common law, to this very day “the glory of the English law” and “the most transcendant privilege which any subject can enjoy,” to use the words of Blackstone, Bk. 3, p. 379. And the additur principle is without general acceptance in this country, and for the given reasons. See annotation to Dimick in 95 A. L. R. 1163; Burdict v. Missouri Pac. Ry. Co., 123 Mo. 227, 27 S. W. 453, 26 L. R. A. 384 (Sup. Ct. 1894); also 39 Am. Jur. 206; 3 Am. Jur. 688. It is a doctrine of the civil law. Southall v. Smith, 151 La. 967, 92 So. 402, 27 A. L. R. 1194 (Sup. Ct. 1922); Stoehr v. Payne, 132 La. 213, 61 So. 206, 44 L. R. A., N. S. 604 (Sup. Ct. 1913). The question is one of constitutional power rather than procedural expediency.

Ho one would contend that the court has an absolute right to assess unliquidated damages in an action at law for a personal tort; and yet can it be other than that when the court in these circumstances imposes its judgment on the unwilling plaintiff? We are not concerned here with an *88action for liquidated damages, or damages fixed by a mere mathematical calculation from ascertained data or capable of certain computation on the record made, or a submission to the court without a jury on a stipulation of the facts. See 3 Am. Jur., Appeal and Error, section 1180.

If the trial judge has the power asserted here, so also is it the province of this court on a review of the sufficiency or insufficiency of an award by a jury. The issue of the weight of the evidence is now cognizable on appeal. Hager v. Weber, supra. R. R. 1:5 — 3 provides that a verdict of a jury “shall be set aside as against the weight of the evidence if, having given due regard to the opportunity of the trial court and the jury to pass upon the credibility of the witnesses, it clearly and convincingly appears that the verdict was the result of mistake, partiality, prejudice or passion.” And yet this court does not undertake to supply the deficiency in the assessment of the damages by the trial judge, nor remand the cause for a reassessment by the judge, but directs a new jury trial limited to damages. .

I concur in this result.

Mr. Justice Oliphant joins in this opinion.

Hehbr and Oliphant, JJ., concurring in result.

For reversal — Chief Justice Vanderbilt, and Justices I-Ieher, Oliphant, Burling, Jacobs and WeintrauB' — 6.

For affirmance — Hone.

Justice Thomas

delivered the opinion of the Court.

Ordinarily, a party in a civil jury trial that believes the evidence is legally insufficient to support an adverse jury verdict will seek a judgment as a matter of law by filing a motion pursuant to Federal Rule of Civil Procedure 50(a) before submission of the case to the jury, and then (if the Rule 50(a) motion is not granted and the jury subsequently decides against that party) a motion pursuant to Rule 50(b). In this case, however, the respondent filed a Rule 50(a) motion before the verdict, but did not file a Rule 50(b) motion after the verdict. Nor did respondent request a new trial under Rule 59. The Court of Appeals nevertheless proceeded to review the sufficiency of the evidence and, upon a finding that the evidence was insufficient, remanded the case for a new trial. Because our cases addressing the requirements of Rule 50 compel a contrary result, we reverse.

*397I

The genesis of the underlying litigation in this case was ConAgra’s attempt to enforce its patent for “A Method for Browning Precooked Whole Muscle Meat Products,” U. S. Patent No. 5,952,027 (’027 patent). In early 2000, ConAgra issued a general warning to companies who sold equipment and processes for browning precooked meats explaining that it intended to “ ‘aggressively protect all of [its] rights under [the ’027] patent.’” 375 F. 3d 1341, 1344 (CA Fed. 2004). Petitioner Unitherm sold such processes, but did not receive ConAgra’s warning. ConAgra also contacted its direct competitors in the precooked meat business, announcing that it was “ ‘making the ’027 Patent and corresponding patents that may issue available for license at a royalty rate of 100 per pound.’” Id., at 1345. Jennie-O, a direct competitor, received ConAgra’s correspondence and undertook an investigation to determine its rights and responsibilities with regard to the ’027 patent. Jennie-0 determined that the browning process it had purchased from Unitherm was the same as the process described in the ’027 patent. Jennie-0 further determined that the ’027 patent was invalid because Unitherm’s president had invented the process described in that patent six years before ConAgra filed its patent application.

Consistent with these determinations, Jennie-0 and Uni-therm jointly sued ConAgra in the Western District of Oklahoma. As relevant here, Jennie-0 and Unitherm sought a declaration that the ’027 patent was invalid and unenforceable, and alleged that ConAgra had violated §2 of the Sherman Act, ch. 647,26 Stat. 209, as amended, 15 U. S. C. §2, by attempting to enforce a patent that was obtained by committing fraud on the Patent and Trademark Office (PTO). See Walker Process Equipment, Inc. v. Food Machinery & Chemical Corp., 382 U. S. 172, 174 (1965) (holding that “the enforcement of a patent procured by fraud on the Patent Office may be violative of §2 of the Sherman Act provided *398the other elements necessary to a §2 case are present”). The District Court construed the ’027 patent and determined that it was invalid based on Unitherm’s prior public use and sale of the process described therein. 35 U. S. C. § 102(b). After dismissing Jennie-0 for lack of antitrust standing, the District Court allowed Unitherm’s Walker Process claim to proceed to trial. Prior to the court’s submission , of the case to the jury, ConAgra moved for a directed verdict under Rule 50(a) based on legal insufficiency of the evidence. The District Court denied that motion.1 The jury returned a verdict for Unitherm, and ConAgra neither renewed its motion for judgment as a matter of law pursuant to Rule 50(b), nor moved for a new trial on antitrust liability pursuant to Rule 59.2

On appeal to the Federal Circuit, ConAgra maintained that there was insufficient evidence to sustain the jury’s Walker Process verdict. Although the Federal Circuit has concluded that a party’s “failure to present the district court with a post-verdict motion precludes appellate review of sufficiency of the evidence,” Biodex Corp. v. Loredan Biomedical, Inc., 946 F. 2d 850, 862 (1991), in the instant case it was bound to apply the law of the Tenth Circuit, 375 F. 3d, at 1365, n. 7 (“On most issues related to Rule 50 motions . . . we generally apply regional circuit law unless the precise *399issue being appealed pertains uniquely to patent law”). Under Tenth Circuit law, a party that has failed to file a postverdict motion challenging the sufficiency of the evidence may nonetheless raise such a claim on appeal, so long as that party filed a Rule 50(a) motion prior to submission of the case to the jury. Cummings v. General Motors Corp., 365 F. 3d 944, 950-951 (2004). Notably, the only available relief in such a circumstance is a new trial. Id., at 951.

Freed to examine the sufficiency of the evidence, the Federal Circuit concluded that, although Unitherm had presented sufficient evidence to support a determination that ConAgra had attempted to enforce a patent that it had obtained through fraud on the PTO, 375 F. 3d, at 1362, Uni-therm had failed to present evidence sufficient to support the remaining elements of its antitrust claim. Id., at 1365 (“Unitherm failed to present any economic evidence capable of sustaining its asserted relevant antitrust market, and little to support any other aspect of its Section 2 claim”). Accordingly, it vacated the jury’s judgment in favor of Uni-therm and remanded for a new trial. We granted certiorari, 543 U. S. 1186 (2005), and now reverse.

II

Federal Rule of Civil Procedure 50 sets forth the procedural requirements for challenging the sufficiency of the evidence in a civil jury trial and establishes two stages for such challenges — prior to submission of the case to the jury, and after the verdict and entry of judgment. Rule 50(a) allows a party to challenge the sufficiency of the evidence prior to submission of the case to the jury, and authorizes the district court to grant such motions at the court’s discretion:

“(a) Judgment as a Matter op Law.

“(1) If during a trial by jury a party has been fully heard on an issue and there is no legally sufficient evi-dentiary basis for a reasonable jury to find for that party on that issue, the court may determine the issue against *400that party and may grant a motion for judgment as a matter of law against that party with respect to a claim or defense that cannot under the controlling law be maintained or defeated without a favorable finding on that issue.

“(2) Motions for judgment as a matter of law may be made at any time before submission of the case to the jury. Such a motion shall specify the judgment sought and the law and the facts on which the moving party is entitled to the judgment.”

Rule 50(b), by contrast, sets forth the procedural requirements for renewing a sufficiency of the evidence challenge after the jury verdict and entry of judgment.

“(b) Renewing Motion for Judgment After Trial; Alternative Motion for New Trial. If, for any reason, the court does not grant a motion for judgment as a matter of law made at the close of all the evidence, the court is considered to have submitted the action to the jury subject to the court’s later deciding the legal questions raised by the motion. The movant may renew its request for judgment as a matter of law by filing a motion no later than 10 days after entry of judgment — and may alternatively request a new trial or join a motion for a new trial under Rule 59. In ruling on a renewed motion, the court may:

“(1) if a verdict was returned:

“(A) allow the judgment to stand,

“(B) order a new trial, or

“(C) direct entry of judgment as a matter of law ....” .

This Court has addressed the implications of a party’s failure to file a postverdict motion under Rule 50(b) on several occasions and in a variety of procedural contexts. This Court has concluded that, “[i]n the absence of such a motion” an “appellate court [is] without power to direct the District *401Court to enter judgment contrary to the one it had permitted to stand.” Cone v. West Virginia Pulp & Paper Co., 330 U. S. 212, 218 (1947). This Court has similarly concluded that a party’s failure to file a Rule 50(b) motion deprives the appellate court of the power to order the entry of judgment in favor of that party where the district court directed the jury’s verdict, Globe Liquor Co. v. San Roman, 332 U. S. 571 (1948), and where the district court expressly reserved a party’s preverdict motion for a directed verdict and then denied that motion after the verdict was returned, Johnson v. New York, N. H. & H. R. Co., 344 U. S. 48 (1952). A postverdiet motion is necessary because “[djetermination of whether a new trial should be granted or a judgment entered under Rule 50(b) calls for the judgment in the first instance of the judge who saw and heard the witnesses and has the feel of the case which no appellate printed transcript can impart.”3 Cone, supra, at 216. Moreover, the “requirement of a timely 'application for judgment after verdict is not an idle motion” because it “is ... an essential part of the rule, firmly grounded in principles of fairness.” Johnson, supra, at 53.

The foregoing authorities lead us to reverse the judgment below. Respondent correctly points out that these authorities address whether an appellate court may enter judgment in the absence of a postverdict motion, as opposed to whether an appellate court may order a new trial (as the Federal Cir*402cuit did here). But this distinction is immaterial. This Court’s observations about the necessity of a postverdict motion under Rule 50(b), and the benefits of the district court’s input at that stage, apply with equal force whether a party is seeking judgment as a matter of law or simply a new trial. In Cone, this Court concluded that, because Rule 50(b) permits the district court to exercise its discretion to choose between ordering a new trial and entering judgment, its “appraisal of the bona fides of the claims asserted by the litigants is of great value in reaching a conclusion as to whether anew trial should be granted.” ' 330 U. S., at 216 (emphasis added). Similarly, this Court has determined that a party may only pursue on appeal a particular avenue of relief available under Rule 50(b), namely, the entry of judgment or a new trial, when that party has complied with the Rule’s filing requirements by requesting that particular relief below. See Johnson, supra, at 54 (“Respondent made a motion to set aside the verdict and for new trial within the time required by Rule 50(b). It failed to comply with permission given by 50(b) to move for judgment n. o. v. after the verdict. In this situation respondent is entitled only to a new trial, not to a judgment in its favor”).4

*403Despite the straightforward language employed in Cone, Globe Liquor, and Johnson, respondent maintains that those cases dictate affirmance here, because in each of those cases the litigants secured a new trial. But in each of those cases the appellants moved for a new trial postverdict in the District Court, and did not seek to establish their entitlement to a new trial solely on the basis of a denied Rule 50(a) motion. See Cone, swpra, at 213 (noting that respondent moved for a new trial);5 Globe Liquor, supra, at 572 (“The *404respondents ... moved for a new trial on the ground ... that there were many contested issues of fact”). Indeed, Johnson concluded that respondent was only entitled to a new trial by virtue of its motion for such “within the time required by Rule 50(b).” 344 U. S., at 54. Accordingly, these outcomes merely underscore our holding today — a party is not entitled to pursue a new trial on appeal unless that party makes an appropriate postverdict motion in the district court.

Our determination that respondent’s failure to comply with Rule 50(b) forecloses its challenge to the sufficiency of the evidence is further validated by the purported basis of respondent’s appeal, namely, the District Court’s denial of respondent’s preverdict Rule 50(a) motion. As an initial matter, Cone, Globe Liquor, and Johnson unequivocally establish that the precise subject matter of a party’s Rule 50(a) motion — namely, its entitlement to judgment as a matter of law — cannot be appealed unless that motion is renewed pursuant to Rule 50(b). Here, respondent does not seek to pursue on appeal the precise claim it raised in its Rule 50(a) motion before the District Court — namely, its entitlement to judgment as a matter of law. Rather, it seeks a new trial based on the legal insufficiency of the evidence. But if, as in Cone, Globe Liquor, and Johnson, a litigant that has failed to file a Rule 50(b) motion is foreclosed from seeking the relief it sought in its Rule 50(a) motion — i. e., the entry of judgment — then surely respondent is foreclosed from seeking a new trial, relief it did not and could not. seek in its preverdict motion. In short, respondent never sought a new trial before the District Court, and thus forfeited its right to do so on appeal. Yakus v. United States, 321 U. S. 414, 444 (1944) (“No procedural principle is more familiar to this Court than that a . . . right may be forfeited ... by the *405failure to make timely assertion of the right before a tribunal having jurisdiction to determine it”).

The text of Rule 50(b) confirms that respondent’s prever-dict Rule 50(a) motion did not present the District Court with the option of ordering a new trial. That text provides that a district court may only order a new trial on the basis of issues raised in a preverdict Rule 50(a) motion when “ruling on a renewed motion” under Rule 50(b). Accordingly, even if the District Court was inclined to grant a new trial on the basis of arguments raised in respondent’s preverdict motion, it was without the power to do so under Rule 50(b) absent a postverdict motion pursuant to that Rule. Consequently, the Court of Appeals was similarly powerless.

Similarly, the text and application of Rule 50(a) support our determination that respondent may not challenge the sufficiency of the evidence on appeal on the basis of the District Court’s denial of its Rule 50(a) motion. The Rule provides that “the court may determine” that “there is no legally sufficient evidentiary basis for a reasonable jury to find for [a] party on [a given] issue,” and “may grant a motion for judgment as a matter of law against that party ....” (Emphasis added.) Thus, while a district court is permitted to enter judgment as a matter of law when it concludes that the evidence is legally insufficient, it is not required to do so. To the contrary, the district courts are, if anything, encouraged to submit the case to the jury, rather than granting such motions. As Wright and Miller explain:

“Even at the close of all the evidence it may be desirable to refrain from granting a motion for judgment as a matter of law despite the fact that it would be possible for the district court to do so. If judgment as a matter of law is granted and the appellate court holds that the evidence in fact was sufficient to go to the jury, an entire new trial must be had. If, on the other hand, the trial court submits the case to the jury, though it thinks the evidence insufficient, final determination of the case is *406expedited greatly. If the jury agrees with the court’s appraisal of. the evidence, and returns a verdict for the party who moved for judgment as a matter of law, the case is at an end. If the jury brings in a different verdict, the trial court can grant a renewed motion for judgment as a matter of law. Then if the appellate court holds that the trial court was in error in its appraisal of the evidence, it can reverse and order judgment on the verdict of the jury, without any need for a new trial. For this reason the appellate courts repeatedly have said that it usually is desirable to take a verdict, and then pass on the sufficiency of the evidence on a post-verdict motion.” 9A Federal Practice §2533, at 319 (footnote omitted).

Thus, the District Court’s denial of respondent’s preverdict motion cannot form the basis of respondent’s appeal, because the denial of that motion was not error. It was merely an exercise of the District Court's discretion, in accordance with the text of the Rule and the accepted practice of permitting the jury to make an initial judgment about the sufficiency of the evidence. The only error here was counsel’s failure to file a postverdict motion pursuant to Rule 50(b).6

*407* H= *

For the foregoing reasons, we hold that since respondent •failed to renew its preverdict motion as specified in Rule 50(b), there was no basis for review of respondent’s sufficiency of the evidence challenge in the Court of Appeals. The judgment of the Court of Appeals is reversed.7

It is so ordered.

Justice Stevens,

with whom Justice Kennedy joins,

dissenting.

Murphy’s law applies to trial lawyers as well as pilots. Even an expert will occasionally blunder. For that reason Congress has preserved the federal appeals courts’ power to correct plain error, even though trial counsel’s omission will ordinarily give rise to a binding waiver. This is not a case, in my view, in which the authority of the appellate court is limited by an explicit statute or controlling rule. The spirit of the Federal Rules of Civil Procedure favors preservation of a court’s power to avoid manifestly unjust results in exceptional cases. See Johnson v. New York, N. H. & H. R. Co., 344 U. S. 48, 62 (1952) (Frankfurter, J., dissenting) (“ ‘Procedure is the means; full, equal and exact enforcement of substantive law is the end’” (quoting Pound, The Etiquette of Justice, 3 Proceedings Neb. St. Bar Assn. 231 (1909))). Moreover, we have an overriding duty to obey statutory commands that unambiguously express the intent of Congress even in areas such as procedure in which we may have special expertise.

Today, relying primarily on a case decided in March 1947, Cone v. West Virginia Pulp & Paper Co., 330 U. S. 212, and a case decided in January 1948, Globe Liquor Co. v. San *408 Roman, 332 U. S. 571, the Court holds that the Court of Appeals was “powerless” to review the sufficiency of the evidence supporting the verdict in petitioner’s favor because respondent failed to file proper postverdict motions pursuant to Rules 50(b) and 59 of the Federal Rules of Civil Procedure in the trial court. Ante, at 405. The majority’s holding is inconsistent with a statute enacted just months after Globe Liquor was decided. That statute, which remains in effect today, provides:

“The Supreme Court or any other court of appellate jurisdiction may affirm, modify, vacate, set aside or reverse any judgment, decree, or order of a court lawfully brought before it for review, and may remand the cause and direct the entry of such appropriate judgment, decree, or order, or require such further proceedings to be had as may be just under the circumstances.” 28 U. S. C. §2106.

Nothing in Rule 50(b) limits this statutory grant of power to appellate courts; while a party’s failure to make a Rule 50(b) motion precludes the district court from directing a verdict in that party’s favor, the Rule does not purport to strip the courts of appeals of the authority to review district court judgments or to order such relief as “may be just under the circumstances.” Nor do general principles of waiver or forfeiture have that effect. Cf. ante, at 404-405. It is well settled that a litigant’s waiver or forfeiture of an argument does not, in the absence of a contrary statutory command, preclude the courts of appeals from considering those arguments. See Singleton v. Wulff, 428 U. S. 106, 121 (1976). Arguments raised for the first time on appeal may be entertained, for example, if their consideration would prevent manifest injustice. Ibid. *

*409For the reasons articulated by the Court in Cone, 330 U. S., at 216, it may be unfair or even an abuse of discretion for a court of appeals to direct a verdict in favor of the party that lost below if that party failed to make a timely Rule 50(b) motion. Likewise, it may not be “just under the circumstances” for a court of appeals to order a new trial in the absence of a proper Rule 59 motion. Finally, a court of appeals has discretion to rebuff, on grounds of waiver or forfeiture, a challenge to the sufficiency of the evidence absent a proper Rule 50(b) or Rule 59 motion made in the district court. None of the foregoing propositions rests, however, on a determination that the courts of appeals lack “power” to review the sufficiency of the evidence and order appropriate relief under these circumstances, and I can divine no basis for that determination.

I respectfully dissent.