Opinion for the Court filed by Circuit Judge ROGERS.
Teva Pharmaceuticals and Purepac Pharmaceutical Company appeal the denial of injunctive relief requiring the Food and Drug Administration (“FDA”) to recognize the dismissal of a declaratory judgment complaint for patent infringement as a “court decision” under the Abbreviated New Drug Application (“ANDA”) statute. See 21 U.S.C. § 355(j)(5)(B)(iv)(II) (Supp. Ill 1997). Appellants are “subsequent” ANDA applicants hoping to market ticlopi-dine tablets, a generic version of the name-brand drug “Ticlid,” used to treat stroke victims. 1 To meet the requirements of the ANDA statute, Teva sued the patent holder 2 in the Central District of California in order to obtain a “court decision” that would start, or trigger, a 180-day period of market exclusivity for the first ANDA applicant, and thereafter allow appellants to market their generic drug. The California court dismissed the complaint for lack of subject-matter jurisdiction after finding, based on the patent holder’s admission of non-infringement, that Teva lacked a reasonable apprehension of suit by the patent holder. The FDA nevertheless refused to recognize the dismissal as a triggering “court decision” under the ANDA statute. Because we conclude that the FDA’s refusal was arbitrary and capricious inasmuch as the FDA has taken an inconsistent position in another case and failed to explain adequately the inconsistency, we reverse and remand the case to the district court to determine anew whether injunctive relief is appropriate.
I.
The statutory background is succinctly summarized as follows. In 1984, Congress amended the Food and Drug Act in order to expedite the approval of generic versions of name-brand drugs that already have FDA approval, thus making available more low-cost generic drugs. See Drug Price Competition & Patent Term Restoration Act of 1984, Pub.L. No. 98-417, tit. 1, 98 Stat. 1585 (1984) (codified as amended at 21 U.S.C. § 355 (1994 & Supp. III 1997)); see also H.R. Rep. No. 98-857, Part 1, at 14 (1984), reprinted in 1984 U.S.C.C.A.N. 2647, 2647. Under the so-called Hatch-Waxman amendments, an abbreviated new drug application process allows applicants, upon meeting certain requirements, to proceed more quickly to the marketplace. The ANDA applicant must show that: (i) the use of the drug has been previously approved; (ii) the new drug contains the same active ingredient(s) as the previously .approved drug, or document the differences; (iii) the new drug has the same route of administration, dosage form, and strength of the previously approved drug, or document the differences; (iv) the new drug is the bioequivalent or has the same therapeutic effect as the previously *1005 approved drug; (v) the new drug has the same labeling as the previously approved drug, or the differences are approved; and (vi) it has complied with other statutory requirements, which include providing a full list of articles used as components, a full statement of composition, samples of the drug, labeling specimens, and a description of manufacturing, processing, and packaging. See 21 Ú.S.C. § 355(j)(2).
To avoid the patent infringement problems inherent in such a statutory scheme, the ANDA applicant must provide the FDA with a certifícate establishing that the marketing of the generic drug will not infringe the patent for the listed drug. To this end, the applicant must certify that: (I) the patent information has not been filed, (II) the patent has expired, (III) the patent will expire on a specified date, or (IV) the “patent is invalid or will not be infringed by the manufacture, use, or sale of the new drug for which the application is submitted.” Id. § 355(j)(2)(A)(vii). As part of a certification under Paragraph IV, the ANDA applicant must notify the patent holder and approved applicants of its application and include a statement of the factual and legal basis for the applicant’s opinion that the patent is not valid or will not be infringed. See id. § 355(j)(2)(B). Under FDA regulations, the applicant may also certify that the patent is unenforceable. See 21 C.F.R. § 314.94(a)(12)(i)(A)(4) (Westlaw 1999).
ANDA applicants who submit Paragraph IV certifications are subject to a “market-exclusivity provision,” see 21 U.S.C. § 355(j)(5)(B)(iv), under which previous applicants are granted 180 days during which subsequent applications cannot be approved. 3 This period is started, or triggered, by the earlier of (1) the date the Secretary of Health and Human Services receives notification from the previous applicant of the first commercial marketing of its drug or (2) the date of a “decision of a court” in a patent or declaratory judgment action “holding” that the patent is either “invalid or not infringed.” Id.; see also id. § 355(j)(5)(B)(iii) (describing suits for patent infringement or declaratory judgment).
Heretofore, the court invalidated the FDA’s “successful defense” requirement, whereby the first ANDA applicant could obtain 180 days of market exclusivity only after successfully defending a patent lawsuit.
See Mova Pharmaceutical Corp. v. Shalala,
II.
Teva challenges the denial of injunctive relief on the principal ground that the FDA’s refusal to treat the dismissal of Teva’s declaratory judgment action as a triggering “court decision” is inconsistent with the ANDA statute and hence, the *1006 district court erred in ruling that Teva had failed to demonstrate a likelihood of success on the merits. Basically, Teva contends that the California dismissal is functionally equivalent to a final decision of noninfringement and unenforceability on the merits because it was based on the patent holder’s express representation to Teva and the California court that Teva’s formulation did not infringe the patent and that the patent holder would not sue Teva for infringement. Indeed, Teva goes so far as to maintain that its interpretation of the statute is the only possible alternative to the FDA’s impermissible construction under the circumstances of this case; otherwise, subsequent ANDA applicants’ efforts to use the Hatch-Waxman procedure could be thwarted anytime a patent holder stated that it did not intend to enforce its patent, thus preventing the courts from exercising subject matter jurisdiction to issue the holding of noninfringement that the FDA’s position requires.
According to Teva’s complaint, on June 20, 1997, Teva filed its ANDA to market ticlopidine, a generic version of the drug •“Ticlid.” While it awaited tentative approval of its application, Teva sued Syntex, seeking a declaratory judgment of nonin-fringement of Syntex’s patent for a finished dosage formulation of ticlopidine tablets. 4 On the same day, Syntex sent Teva a letter expressing the opinion that Teva would not infringe Syntex’s patent, declaring: “We will make no claim of patent infringement based on the sale of ticlopi-dine hydrochloride tablets having the formulation you have disclosed to us.” Thereafter, Teva prepared a joint motion for entry of consent judgment that would hold Syntex’s patent not infringed; but Syntex instead moved to dismiss the complaint for lack of subject-matter jurisdiction, explaining:
Given Syntex’s express assurance that it would not bring suit against Teva on the ’592 patent, Teva can have no reasonable apprehension that it will face a lawsuit for infringement of the ’592 patent. Without such reasonable apprehension, no actual case or controversy exists of sufficient immediacy or reality to base jurisdiction over Teva’s declaratory judgment claim.
Accompanying the motion was a declaration by John Parise, counsel for Syntex, referring to the June 8, 1998, letter that Syntex sent Teva stating that Syntex would make no claim of patent infringement against Teva. Noting that under Federal Rule Civil Procedure 12(b)(1) the district court could consider materials outside of the pleadings,
see Dreier v. United States,
On October 29, 1998, the FDA tentatively approved Teva’s ANDA to market ticlo-pidine. However, the FDA informed Teva that because there was a previous ANDA applicant and neither commercial marketing nor a court decision had occurred, its application was ineligible for final approval. Teva attempted to persuade the FDA that the California dismissal satisfied the “court decision” requirement, but the FDA did not respond to Teva’s request for an effective approval date and on December 2, 1998, notified Teva that it refused to meet to discuss the issue. Teva then filed *1007 the instant lawsuit in district court for a declaratory judgment that Teva is entitled to have its ANDA become effective on February 10, 1999 (180 days after the California dismissal), an injunction making Teva’s ANDA effective on that date, and a temporary restraining order to forestall the FDA from approving the first ANDA application if such approval would give the first applicant any exclusive marketing beyond February 10,1999.
The district court declined to award in-junctive relief. It concluded for three reasons that Teva could not demonstrate a likelihood of success on the merits. First, the district court ruled that the California dismissal did not fall within the plain language of § 355(j)(5)(B)(iv)(II), and, second, that even if Teva could show that the statute was ambiguous, it was unlikely to succeed in showing that the FDA’s interpretation was impermissible, or that Teva’s interpretation was the only permissible alternative. The district court concluded, third, that Teva’s reliance on patent law decisions of the Federal Circuit was misplaced because they had no direct bearing on the “court decision” provision in ANDA. Consequently, the district court reasoned, in view of language in decisions of this court, 5 that the triggering “court decision” provision required nothing less than a decision on the merits. The district court was also unpersuaded by Teva’s arguments concerning irreparable harm, injury to the other parties, and the public interest. 6
III.
On appeal, Teva contends that the district court erred in denying injunctive relief because the California dismissal qualified as a “court decision” under § 355(j)(5)(B)(iv)(II) and the FDA’s refusal to recognize the dismissal as such was arbitrary and capricious, an abuse of discretion, and based on an unreasonable and impermissible interpretation of the statute. Our review of the denial of injunctive relief is for abuse of discretion, but we review
de novo
the district court’s conclusion of law, namely that Teva was unlikely to prevail in its challenge to the FDA’s refusal to treat the California dismissal as a triggering “court decision.”
See Mova,
The FDA maintains that its interpretation of the “court decision” provision is entitled to deference under
Chevron U.S.A., Inc. v. Natural Resources Defense Council, Inc.,
First, the FDA concedes that its refusal to recognize the California dismissal as a triggering “court decision” is not compelled by the statutory language. The statute requires a “decision of a court holding the patent ... invalid or not infringed.”
See
21 U.S.C. § 355(j)(5)(B)(iv)(II). A “decision” can take several forms, including final judg
*1008
ment after a fall trial, summary judgment or partial summary judgment, or even a dismissal for failure to state a cause of action. The term “holding,” most often contrasted with the term “dicta,” is also susceptible to interpretation.
See, e.g., Seminole Tribe of Fla. v. Florida,
But the California dismissal cannot be classified as a typical dismissal for lack of subject matter jurisdiction. Although, as a general rule, such a dismissal has no pre-clusive effect because the court lacked authority or competence to hear and decide the case,
see Prakash v. American Univ.,
The FDA and intervenor TorPharm (the first ANDA filer) conceded at oral argument that the California dismissal prevents Syntex from suing Teva for infringement. The conclusion that the California dismissal has estoppel effect is supported by the decisions of the United States Court of Appeals for the Federal Circuit. That court has recognized that a dismissal of a declaratory judgment action for lack of a case or controversy due to the patent holder’s disavowal of any intent to sue for infringement has preclusive effect.
See Super Sack Mfg. Corp. v. Chase Packaging Corp.,
Put otherwise, the California dismissal appears to meet the requirements of a triggering “court decision” because that court had to make a predicate finding with respect to whether Syntex would ever sue Teva for infringement in order to conclude that there was no case or controversy between the parties. In dismissing Teva’s complaint for lack of subject matter jurisdiction, the California court expressly found that Teva “lacks a reasonable apprehension of suit by Syntex for infringement of [its patent].” According to Syntex’s motion to dismiss Teva’s complaint, that finding could only have been based on the patent holder’s declaration of counsel and its June 8th letter to Teva. Although the dismissal was not a judgment on the merits after consideration of evidence presented by the parties, there was no need for such a procedure here because the dismissal sufficed to estop Syntex from suing Teva for patent infringement.
See Super Sack,
Second, it is unclear that a triggering “court decision” need explicitly hold the patent at issue is “invalid” or is “not infringed” in order to trigger the 180-day period of market exclusivity. Both the FDA and the Federal Circuit recognize that a certification that a patent is “unenforceable” suffices for purposes of the Paragraph IV certification,
see
21 C.F.R. § 314.94(a)(12)(i)(A)(4);
Merck & Co. v. Danbury Pharmacol, Inc.,
íntervenors’ attempt to assert that un-enforceability, which is included in the regulation, and estoppel, which is presented here, should be treated differently under § 355(j)(5)(B)(iv)(II) is unpersuasive. Although it is true that a determination of unenforceability, such as for inequitable conduct, applies generally, preventing the patent holder from enforcing the patent against any entity,
see Elk Corp. of Dallas v. GAF Bldg. Materials Corp.,
Third, the FDA’s treatment of the California dismissal appears contrary to the FDA’s “Guidance for Industry” in two respects.
Cf. Cherokee Nation of Okla. v. Babbitt,
How the FDA can justify this approach to Teva’s interpretation of the California dismissal in light of its treatment of other cases remains a mystery; presumably in a “case-by-case” analysis the FDA is obligated to explain such differences.
See ANR Pipeline Co. v. FERC,
Second, the FDA’s response to Teva’s interpretation of the “court decision” requirement is not easily viewed as “regulating] directly from the statute,” as the FDA committed to do in its “Guidance for Industry.” The FDA “acknowledges that its current interpretation of the court decision trigger is narrower than the statute may be able to support.... [and] that Teva’s interpretation of the court decision trigger may be permissible.” Yet if the FDA’s interpretation of section 355(j)(5)(B)(iv)(II) is “narrower than the statute [is] able to support,” then its interpretation cannot stand without justification because the FDA must interpret the statute to avoid absurd results and further congressional intent.
See Robinson v. Shell Oil Co.,
As a result of the FDA’s current construction of the “court decision” requirement and its treatment of Teva’s application, generic ticlopidine tablets were not available in the marketplace for a number of months despite the fact that appellants both stood ready to market them. Syntex remained the exclusive manufacturer of “Ticlid,” and the first ANDA applicant’s market exclusivity period had not begun because the FDA had yet to approve that applicant’s filing. On July 1, 1999, the FDA finally approved TorPharm’s ANDA, and TorPharm commenced marketing on July 6, so now at least one generic version of ticlopidine tablets is available.
8
Yet, this series of events may well not have been what Congress contemplated in enacting the Hatch-Waxman amendments to expedite generic drug approvals.
See
H.R.Rep. No. 98-857, Part 1, at 14-15,
*1012
reprinted in
1984 U.S.C.C.A.N. 2647, 2647-48;
cf. Mova,
Accordingly, we reverse, and because our conclusion could well affect the district court’s evaluation of appellants’ other arguments concerning harm, injury, and the public interest, we remand the case to the district court to consider anew the request for injunctive relief.
Notes
. Purepac has joined in the argument presented in the brief filed by Teva, having been unsuccessful in a previous challenge to the FDA's interpretation of the ANDA statute in
Purepac Pharmaceutical Co. v. Friedman,
. Syntex (U.S.A.), Inc., the holder of Patent No. 4,591,592 (" '592 patent” or "patent”) that covers a finished dosage formulation of a ticlopidine tablet, but not the active pharmaceutical ingredient ticlopidine hydrochloride, and Hoffmann-LaRoche Laboratories Inc., which markets ticlopidine tablets under the brand-name "Ticlid,” are two of the interve-nors. For ease of reference we refer to Syn-tex and Hoffmann-LaRoche collectively as "Syntex.” Also intervening is TorPharm, which has identified itself as the first applicant to file its ANDA.
. As interpreted by the FDA, the statute does not guarantee the first ANDA applicant a 180-day period of exclusivity. The court-decision trigger can be activated by any subsequent ANDA applicant’s litigation whether or not the first applicant has enjoyed a period of exclusivity. See Guidance for Industry: 180-Day Generic Drug Exclusivity Under the Hatch-Waxman Amendments to the Federal Food, Drug and Cosmetic Act 5 (June 1998).
. Syntex had previously sued Teva and others for possible infringement of its process patent for ticlopidine, but voluntarily dismissed its complaint against Teva without prejudice once Teva revealed its process. That litigation was unrelated to the formulation patent at issue in the declaratory judgment action.
.
See Purepac,
.
See Mova,
. See also 5A Charles A. Wright & Arthur R. Miller, Federal Practice and Procedure § 1350, at 225 (2d ed. 1990).
. The FDA's approval of TorPharm’s ANDA does not moot this appeal because Teva sought a preliminary injunction against the FDA compelling it to deem Teva's application effective as of February 10, 1999. Though Teva will be able to market its ticlopidine tablet 180 days after July 6 without fail, in the interim Teva and Purepac face continued harm because of their denied access to the market,
see Byrd v. EPA,
