Opinion for the Court filed by Circuit Judge WILLIAMS.
We review here an award of attorneys’ fees incurred by Public Citizen Health Research Group in an effort to force the Food & Drug Administration to require a warning of Reye’s Syndrome on aspirin labels. The FDA eventually imposed the requirement, and the district court found that even though the lawsuit was never decided on the merits, it was enough of a “catalyst” for Public Citizen to be considered a “prevailing party” under EAJA, the Equal Access to Justice Act, 28 U.S.C. § 2412 (1988). We affirm that finding, but must reverse his award of fees on two other points. First, in finding the government’s position
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not “substantially justified” after 1984, the district court used a less generous standard (to the government) than is demanded by the Supreme Court’s decision in
Pierce v. Underwood,
I
Reye’s Syndrome is a rare illness that usually afflicts children and teenagers recovering from viral infections. It causes death in 20-30 percent of all cases, and permanent brain damage in many others. See
Public Citizen Health Research Group v. Commissioner, Food & Drug Admin.,
A good deal of backing and filling ensued. Three months after Public Citizen brought suit, the Secretary of HHS issued a press release indicating that he would propose requiring a warning label on products with salicylates. Public Citizen then moved for summary judgment. A month later, the Secretary announced that he was initiating the process of requiring a warning by submitting an appropriate regulation to OMB for review. A little later, however, while the summary judgment motion was still pending, the Secretary reversed field on the basis of a switch by the American Academy of Pediatrics, which dropped its earlier support for a mandatory warning label and instead suggested that more evidence was needed. At this point the FDA decided to commission a comprehensive study.
The district court proceeded to dismiss the suit for want of both ripeness and finality in the FDA’s actions. The court of appeals affirmed the dismissal on the “mis-branding” claim but remanded for the district court to consider Public Citizen’s claim of unreasonable delay. See
Public Citizen,
In January 1985 the FDA released the results of a pilot study designed as the first phase of the comprehensive inquiry. Although the pilot was on a small scale and suffered from other methodological frailties, a committee of the Institute of Medicine (an offshoot of the National Academy of Sciences) found that the data showed a “strong association” between Reye’s Syndrome and the use of aspirin. The Secretary renewed his decision to wait for the results of the final study, but asked the aspirin industry to label its aspirin products voluntarily in the meantime.
Two months later Public Citizen filed a new motion for summary judgment, and the FDA countered with its own. The court heard oral argument in September 1985, and in December, while the motions were still undecided, the FDA proposed a warning requirement. It adopted the regulation in March 1986 (effective June 5, 1986), and Public Citizen moved to have its complaint dismissed, reserving only the issue of attorneys’ fees.
The study initiated in 1982 was completed in November 1986. It confirmed the pilot study, finding a “large, statistically significant association between Reye’s syndrome in children and teenagers and the ingestion of aspirin during previous illnesses.” See Labeling for Oral and Rectal Over-the-Counter Aspirin and Aspirin-Containing Drug Products; Reye Syn *549 drome Warning, 53 Fed.Reg. 21,633 (June 9, 1988).
II
The Equal Access to Justice Act allows a limited class of “prevailing” parties-ones that aren’t too wealthy-to recover attorneys’ fees in suits against the United States unless the United States’s position was “substantially justified." 28 U.S.C. § 2412(d)(1)(A) (1988). We first address the conclusion that plaintiff prevailed, then the issues revolving around the court’s finding that the government was “substantially justified” until the end of 1984 but not thereafter.
A. Prevailing party
A party need not procure a final judgment on the merits in order to be considered a “prevailing party” for fee-shifting purposes. It is enough that the lawsuit was a “causal, necessary, or substantial factor in obtaining the result” plaintiff sought.
Commissioners Court of Medina County, Texas v. United States,
The government would sweep the whole catalyst theory aside on the ground that it cannot apply where there has been a judicial determination on the merits. Normally, of course, that is true; such a decision would itself determine who was prevailing and make the catalyst notion irrelevant. But here, despite its loss on the misbranding claim before this court, Public Citizen on remand was pressing claims that no court had accepted or rejected-the delay claim, on which we remanded, and a revived misbranding claim premised on the argument that the FDA’s voluntary label-ling program provided the final agency action that had been missing before. Thus there was no decision for or against plaintiff that was enough to moot the catalyst issue.
We review the district court’s finding of causation under the “clearly erroneous” standard, see
Perket v. Sec’y of Health and Human Services,
The district court started its discussion of causation by quoting the Supreme Court’s statement in
Hensley v. Eckerhart,
We can find no basis for any standard laxer than tort law’s traditional minimum, “but for” causation, restated for this context: the claimant must show that it is more probable than not that the government would not have performed the desired act absent the lawsuit. See
Environmental Defense Fund, Inc. v. EPA,
It is quite true that in
Save Our Cumberland Mountains Inc. v. Hodel,
The requirement of “but for” causation appears to be relaxed in torts only in two sets of cases. First are those where the law requires multiple negligent defendants,
1
rather than the innocent plaintiff, to bear the risk of uncertainty as to which defendant is causally responsible.
Summers v. Tice,
Plaintiff notes that despite many switches after the filing of the lawsuit, the key switch — the final decision to mandate warnings — came just eleven weeks after oral argument on the cross-motions for summary judgment, an oral argument in which the district court gave Public Citizen’s view a very hospitable reception. See Transcript of Cross Motions for Summary *551 Judgment, Public Citizen Health Research Group v. Commissioner, FDA, Docket No. CV 82-1346 (Sept. 30, 1985). The sequence is highly suggestive.
The government nevertheless faults the district court’s inference of causality by pointing out a discrepancy in its discussion of misbranding and labelling. While the court said that Public Citizen had not prevailed on its misbranding claim, it purported to find that it did so on a “labelling” claim.
This is all the more true in light of Public Citizen’s second claim — that the FDA was delaying unreasonably. This court had hinted at the claim’s having great strength, see
Public Citizen,
Although chronology is important in determining causation, see
Environmental Defense Fund,
The FDA claims that two factors extraneous to the litigation led it to issue the mandatory labelling regulations earlier than it had originally planned: the FDA was being pressured from Congress to move more quickly, and the voluntary labels were causing confusion among consumers because of a lack of uniformity. The legislative action was hardly overpowering. It consisted only of a subcommittee hearing in March 1985, see, e.g., J.A. 158-72, and the introduction of bills, two in February 1985 and one in October 1985, that would have required warning labels, see Proposed Labelling for Oral Aspirin-Containing Drug Products, 50 Fed.Reg. 51,400, 51,402/1 (Dec. 17, 1985). And the district court presumably discounted the government’s suggestion in December 1985 that consumers were confused by the voluntary labelling; the argument was a complete reversal, unexplained by any new data, of its claim at oral argument that the voluntary labelling program was working wonderfully. Compare Transcript of Cross Motions for Summary Judgment, No. CV 82-1346, Public Citizen Health Research Group v. Hayes, Sept. 30, 1985, pages 22-25 (extolling the virtues of the voluntary labelling program); id. at 22:4-5 (“the government is pleased with that voluntary program”) with Proposed Labelling, 50 Fed.Reg. at 51,401-02 (noting that different labels are “likely to be somewhat confusing”). We cannot say that the district court finding was clearly erroneous.
B. Substantially justified
Although we uphold the district court’s determination that Public Citizen prevailed in this litigation, we must remand for it to reassess whether the government’s litigating position was substantially justi
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fied. In finding that the government’s position was not, the district court erroneously relied on a test adopted by this circuit (“slightly more stringent than ‘one of reasonableness,’ ”
Public Citizen,
Even if the district court ultimately concludes that the government’s litigating position was not substantially justified, it may not allow Public Citizen to recover for fees incurred prior to 1985. The district court found (even under the stricter test disapproved in
Pierce)
that the government’s litigating position
was
substantially justified until “late 1984 or early 1985” because prior to that date (when the American Association of Pediatrics published the results of its pilot study) the HHS had before it conflicting expert opinions concerning the nature of the association between Reye’s Syndrome and aspirin.
The district court’s award of attorneys’ fees prior to 1985 was thus premised on the notion that
all
of Public Citizen’s actions in some way caused the ultimate success on the merits. EAJA, however, demands more than conventional fee-shifting statutes. Under EAJA fees are reimbursable only if the government not only lost but had no reasonable basis in law and fact for taking the position it took. See
Pierce,
The district court may have thought it was without power to sever the collectible from the uncollectible fees in light of our decision in
Copeland v. Marshall,
Ill
We uphold the district court’s determination that absent Public Citizen’s suit the *553 FDA would not have promulgated its regulation as early as March 1986. We reverse its award of attorneys’ fees incurred prior to 1985 because the government’s litigating position was substantially justified at least until that point. We remand for the district court to reassess whether the government’s litigating position was substantially justified after 1984 under the standard announced in Pierce.
So ordered.
Notes
. "Negligent" here serves to cover any necessary ingredients of liability apart from causation, e.g., the (non-causation) elements of strict liability for defective products.
