The Federal Circuit’s Approach to the Infringement Analysis in Hatch-Waxman Cases

35 U.S.C. § 271(e)(2) provides that it shall be an act of infringement to submit an Abbreviated New Drug Application (“ANDA”) “if the purpose of such submission is to obtain approval … to engage in the commercial manufacture, use, or sale of a drug … claimed in a patent or the use of which is claimed in a patent before the expiration of such patent.” 35 U.S.C. § 271(e)(2). The statute requires that the infringement analysis focus on what is likely to be sold following FDA approval. Bayer AG v. Biovail Corp., 279 F.3d 1340, 1346 (Fed. Cir. 2002). The governing case law holds that this hypothetical inquiry is grounded in the ANDA application itself, the materials submitted in support thereof, as well as any other relevant evidence submitted by the applicant or patent holder. See, e.g., Bayer AG v. Elan Pharm. Res. Corp., 212 F.3d 1241, 1248-49 (Fed. Cir. 2000) (citing Glaxo, Inc. v. Novopharm, Ltd., 110 F.3d 1562, 1570 (Fed. Cir. 1997)). In a manner analogous to the role of intrinsic evidence in a claim construction analysis, however, the case law is, on the surface at least, also very clear that where the ANDA specification directly addresses and resolves the infringement question, then that analysis will control the infringement determination. See, e.g., Elan Pharm. Res. Corp., 212 F.3d at 1248-50; Ferring B.V. v. Watson Labs., 764 F.3d 1382, 1389-90 (Fed. Cir. 2014) (“Ferring I”); Ferring B.V. v. Watson Labs., 764 F.3d 1401, 1408-09 (Fed. Cir. 2014) (“Ferring II”). However, as reflected in the below discussion of key Federal Circuit case law examining the appropriate analytical approach, and the sorts of evidence properly considered, when assessing infringement in the ANDA context, these seemingly bedrock legal principles in reality fall by the way side and, therefore, neither patentees nor ANDA applicants should allow themselves to be lulled into a false sense of security through reliance on such verbiage.

Glaxo v. Novopharm

In perhaps the most frequently cited case on this issue, Glaxo v. Novopharm, the Federal Circuit affirmed the district court’s finding of no infringement. Glaxo, 110 F.3d at 1570. The relevant patent claims at issue were directed to Form 2 ranitidine HCl (“RHCl”). (RHCl exists in multiple crystalline forms and mixtures thereof, among which forms are those termed Forms 1 and 2 ranitidine.) The API in Novopharm’s ANDA product was Form 1 RHCl, but the finished product specification allowed for a product having purity as low as 90%. Id. at 1564. As the infringement issue was focused on whether or not Novopharm’s proposed ANDA product would contain Form 2 RHCl, the Federal Circuit held that the ANDA did not resolve the infringement issue. Id. at 1569. The Federal Circuit held that, in light of the ambiguity left open by the ANDA itself, the district court was justified in considering biobatch data and analysis of product samples and, based on such data, finding that Novopharm’s ANDA product did not infringe the relevant patent claims. Id. at 1569-70.

Sunovion Pharms. Inc. v. Teva Pharms. USA, Inc.

In Pharms. Inc. v. Teva Pharms. USA, Inc., the Federal Circuit held that Dr. Reddy’s proposed ANDA product infringed patent claims directed to the molecule zopiclone in its dextrorotatory form and containing less than 0.25% of the levorotatory isomer. Sunovion Pharms. Inc. v. Teva Pharms. USA, Inc., 731 F.3d 1271, 1273 (Fed. Cir. 2013). The product specifications in Dr. Reddy’s ANDA allowed for 0.0-0.6% of the levorotatory form of zopiclone. Id. at 1278. The Federal Circuit held that, in this instance, the ANDA directly addressed and resolved the infringement issue in favor of the patentee. Id. at 1278-79. The Sunovion opinion attempts to distinguish Glaxo on the grounds that in Glaxo “the ANDA specification itself did not resolve the question of infringement in the first instance.” Id. at 1279-80. It is unclear, however, how in Sunovion the ANDA specification was said to resolve the infringement inquiry while in Glaxo the ANDA specification was said not to resolve the infringement inquiry. In both cases, the ANDA specification allowed for an infringing product potentially.

Bayer v. Elan

Another oft-cited case in this area is Bayer v. Elan. There, the court held that the ANDA specification directly addressed the infringement issue in favor of the accused infringer. Elan Pharm. Res. Corp., 212 F.3d at 1250. The patent claims at issue were directed to a pharmaceutical composition comprising an effective amount of nifedipine crystals with a specific surface area (“SSA”) of 1.0 to 4 m2/g. Id. at 1245-46. Elan’s ANDA specification indicated that the SSA of the nifedipine crystals in Elan’s proposed ANDA product was to be 5 m2/g or greater. Id. at 1246. This holding would seem to comport with the blackletter principles set out in the governing case law. However, in a related case involving the same ANDA product but in a different strength (60 mg instead of 30 mg of nifedipine), the Federal Circuit refused to affirm the district court’s infringement finding for what, aside from the strength, was the same ANDA product and the same product specification. See Biovail, 279 F.3d at 1346. The court’s opinion reasoned as follows: “[B]ased on Elan’s raw material evidence alone, the district court properly granted summary judgment of non-infringement on Elan’s 30 mg ANDA. In the 60 mg ANDA case, by contrast, Bayer introduced evidence of actual infringement by a commercial tablet made under the specifications of an allegedly identical [in relevant part] ANDA … Unlike the 30 mg ANDA case, Bayer submitted a declaration by Professor Markus Antonietti that Elan’s 30 mg commercial tablet contained nifedipine crystals with a specific surface area of 1.0 to 4 m2/g. According to his declaration, Professor Antonietti performed a ‘gradient separation method’ and an ‘isopycnic separation method’ to determine the nifedipine SSA in the commercial tablets. Using those two methods, he discovered the SSA in the tablets to be, on average, 3.32 m2/g and 3.40 m2/g, respectively.” Biovail Corp., 279 F.3d at 1346. The Federal Circuit’s holding in Biovail is contrary to the frequently referenced blackletter law that, where the ANDA specification directly addresses the infringement question, then it dictates the infringement determination. The practical utility of the Bayer v. Elan case has further been called into doubt more recently in Tyco Healthcare Group LP v. Mutual Pharm. Co., Inc., 762 F.3d 1338 (Fed. Cir. 2014).

Tyco Healthcare Group LP v. Mutual Pharm. Co.

In Tyco Healthcare Group LP v. Mutual Pharm. Co., the patent claims at issue recited, in relevant part, 7.5 mg formulations of temazepam having a SSA between 0.65 and 1.1 m2/g. Tyco Healthcare Group, 762 F.3d at 1341. Mutual’s ANDA product specification required that the SSA of the proposed ANDA product be not less than 2.2 m2/g. Id. at 1340. The district court had found that, despite the fact that the ANDA specification required an SSA outside the scope of the asserted patent claims, it was reasonable for Tyco to proceed with its infringement claims against Mutual. Id. at 1342. As characterized in the Federal Circuit’s opinion, “[t]he evidence showed … that in testing its proposed ANDA product, Mutual had used an outgassing temperature of 40° C, while Tyco had used an outgassing temperature of 105° C in its tests of the product. Because of that difference in temperatures used during the measurement process, the [district] court concluded that it was reasonable for Tyco to proceed with its infringement action.” Id. The Federal Circuit was in agreement on this point, commenting that “it is not unreasonable for a patent owner to allege infringement under section 271(e)(2)(A) if the patent owner has evidence that the as-marketed commercial ANDA product will infringe, even though the hypothetical product specified in the ANDA could not infringe.” Id. at 1344. Federal Circuit cases decided later the same month, however, revert back to the standard, frequently-cited, blackletter principles that where the ANDA specification directly addresses the infringement question, it controls. See Ferring I, 764 F.3d at 1389-90 (“We conclude that the 2014 ANDA specification speaks directly to the question of infringement and would not permit Apotex to market an infringing product. … We concluded [in Bayer v. Elan] that an amended ANDA that addresses the issue of infringement and precludes such infringement is generally dispositive. Here, the conclusion is equally clear – the 2014 ANDA shows that Apotex is not permitted to sell an infringing product.”); Ferring II, 764 F.3d at 1408-09 (“In some cases, the ANDA specification directly resolves the infringement question because it defines a proposed generic product in a manner that either meets the limitations of an asserted patent claim or is outside the scope of such a claim. … In cases in which the ANDA specification does not resolve the infringement question in the first instance, we have endorsed the district court’s reference to relevant evidence, including biobatch data and actual samples of the proposed generic composition that the ANDA filer had submitted to the FDA.”).

Take Away

The key take-away from this body of case law is that, in ANDA cases, patentees and accused infringers alike should be wary of the commonly quoted, ostensibly blackletter, law that where the ANDA specification, on its face, directly resolves the infringement question, then that is the end of the infringement inquiry. Rather, patentees should always be prepared in the event that they need to use additional data, such as biobatch data and/or the results of analytical testing of samples of the ANDA product at issue, to show infringement; and, conversely, ANDA applicants likewise should be prepared to address such additional potential evidence.


Warning & Disclaimer: The pages, articles and comments on do not constitute legal advice, nor do they create any attorney-client relationship. The articles published express the personal opinion and views of the author as of the time of publication and should not be attributed to the author’s employer, clients or the sponsors of

Join the Discussion

3 comments so far.

  • [Avatar for Theodore Chiacchio]
    Theodore Chiacchio
    April 4, 2018 11:57 am

    Thanks for the comment Connor. The CAFC has held that the infringement inquiry must focus on the product that the ANDA applicant will likely market if the ANDA is approved. The court has further noted that infringement may be found despite the ANDA specification if, for example, the ANDA is based on faulty testing or screening procedures. So, to answer your question, an out-of-specification (OOS) ANDA product may still form the basis of an infringement finding. The patentee may also petition FDA to lodge its complaint regarding the OOS ANDA product in an effort to try to block final approval/marketing/sale of the ANDA product.

  • [Avatar for Connor]
    April 3, 2018 11:44 am

    Thanks for the interesting article. So tactically, if the patentee can show that the generic product falls outside the scope of the ANDA, do they submit that information to the FDA to block the generic product from being marketed (unless the ANDA is amended)? Or would they need to file another suit in district court?

  • [Avatar for xtian]
    April 3, 2018 09:34 am

    One thing to also look out for, which may be the basis for some of the apparently diverging cited case law, is that an ANDA filer will file a non-infringing ANDA. The district court case goes to trial, and the ANDA “paper” product is found not to infringe. However, during the trial, the original ANDA “paper” product is found not to meet FDA bioequivalence standards to the reference product. So, the ANDA is amended (typically after trial) and the supplemented ANDA now shows that proposed “new” generic product is infringing. If the Brand can bring this to the attention of the district court, via batch records and the like, then this is where the case law develops that appears to diverge from the black letter law.