United States: US Update: Double Patenting

The law of obviousness-type double patenting continues to evolve in the United States. In early 2017, we discussed how the Federal Circuit's Gilead decision expanded the scope of obviousness-type double patenting (ODP)1. In a split decision, the court held that the ODP analysis must focus on the expiration dates of the patents, not the issue dates, which were previously used2. By focusing on the expiration dates, the court in Gilead found that a later-issued but earlier-expiring patent could be applied as an invalidating ODP reference against an earlier issued but later-expiring patent3. Thus, as the facts in Gilead showed, a first patent with a term completely subsumed within the term of a patently indistinct second patent could shorten the term of exclusivity otherwise available to that second patent regardless of the issue dates of those patents.4 

Gilead dealt with two post-URAA patents that were filed in two separate priority chains (i.e., having different effective filing dates) and therefore naturally had different expiration dates.5, 6  Another common situation in which ODP arises is where two patents share a common priority (e.g., one filed as a continuation of the other) but have different expiration dates due to patent term adjustment (PTA) under 35 U.S.C. §154, which extends the term of a patent due to USPTO delays in prosecution. The Gilead decision raised a question regarding the interplay between ODP and PTA, particularly in situations (unlike Gilead) when the difference in expiration dates is solely due to the PTA of the challenged patent. While the Federal Circuit has not yet directly addressed whether ODP should take precedence over statutorily authorized PTA, it found in the recent "Ezra" decision7 that the judicially created ODP doctrine cannot cut off a statutorily authorized patent term extension (PTE) under 35 U.S.C. §156, which extends the term of a patent covering a product that requires regulatory (e.g., FDA) review before commercialization. 

This article discusses the Ezra decision and analyzes the divergent approaches taken by at least one district court and the Federal Circuit in determining the effects of PTA and PTE on the application of ODP. The article also discusses another recent decision by the Federal Circuit, Breckenridge,8 which separately limits Gilead and holds that ODP cannot truncate the 17-year term of a pre-URAA patent based on a later-issued but earlier expiring post-URAA patent.

The unanswered effect of ODP on PTA

Gilead dealt with two (post-URAA) patents – US Patent Nos. 5,763,483 and 5,952,375 – that belonged to "separate 'chain' of applications" and had different priority dates, as shown in the diagram below.9 

Relying on the different expiration dates of the two patents, the Federal Circuit found that the later-expiring '483 patent was invalid for ODP because its claims were not "patentably distinct" from those in the earlier-expiring '375 patent.10 Gilead did not specifically address whether ODP should apply when the difference in expiration dates is solely because of PTA or PTE, and not due to filing patentably indistinct priority dates (as in Gilead). Following Gilead, one district court in Magna Electronics Inc v TRW Automotive Holdings Corp,11 applied ODP to two patents in the same family that had different expiration dates because one of the patents accrued PTA while the other did not. Without any PTA, both patents would have expired on the same date. But, relying on the reasoning in Gilead that expiration dates control the ODP analysis, the district court used the earlier-expiring patent (without PTA) as an ODP reference against the claims of the later-expiring patent (with PTA).12 Because the asserted claim of the later-expiring patent was patentably indistinct from a claim of the earlier-expiring reference patent, and because the patent owner had not filed a terminal disclaimer for the earlier-issued but later-expiring patent, the court found the asserted claim invalid under ODP. 13,14

The Michigan court in Magna Electronics seems to base its reasoning on another post-Gilead Federal Circuit decision, AbbVie Inc. v Mathilda & Terence Kennedy Institute of Rheumatology Trust15. In the AbbVie case, similar to the situation in Gilead, the difference in patent term was due to the reference and challenged patents having different priority chains.16 Although the panel in AbbVie did not (and did not need to) deal with PTA, it nonetheless commented that: 

"[ODP] is designed to prevent an inventor from securing a second, later-expiring patent for the same invention. That problem still exists [post-URAA]. Patents claiming overlapping subject-matter that were filed at the same time still can have different patent terms due to examination delays at the PTO... So too where, as here, the applicant chooses to file separate applications for overlapping subject-matter and to claim different priority dates for the applications, the separate patents will have different expiration dates since the patent term is measured from the claimed priority date. When such situations arise, the doctrine of obviousness-type double patenting ensures that a particular invention (and obvious variants thereof) does not receive an undue patent term extension." [Id. at 1373  (internal citations omitted).]

According to some, this comment suggests that the judge-made ODP doctrine could override the statutory grant of PTA by either invalidating the PTA-granted patent (as in Magna Electronics), or by truncating the PTA-adjusted term that extends beyond the expiration date of the reference patent (because a terminal disclaimer would be required). The parties in Magna Electronics subsequently settled and did not appeal the decision to the Federal Circuit. As of January 2019, we are not aware of any district court case or Federal Circuit decision that directly addressed this specific issue of PTA and ODP.

The answered effect of ODP on PTE

In Ezra, the Federal Circuit squarely dealt with PTE and held that ODP cannot truncate an otherwise validly extended patent with PTE.17,18 At issue were two Novartis patents that qualified for PTE: US Patent No. 5,604,229, which claims an active compound, and US Patent No. 6,004,565, which claims a method of administering the compound19. As shown below, the '229 patent was filed and issued before the '565 patent was filed (and issued).20 As permitted, Novartis applied for PTE on the '229 patent and was granted five years of extended term.21 With PTE, the '229 patent is set to expire on 18 February 2019, while the '565 patent expired on 23 September 2017. Ezra argued that the '229 patent should be ruled invalid, or otherwise terminally disclaimed for the patent term past the expiration date of the '565 patent. But the court disagreed, holding: ODP "does not invalidate a validly obtained PTE."22 The court stated: 

"If a patent, under its original expiration date without a PTE, should have been (but was not) terminally disclaimed because of obviousness-type double patenting, then this court's obviousness-type double patenting case law would apply, and the patent could be invalidated. However, if a patent, under its pre-PTE expiration date, is valid under all other provisions of law, then it is entitled to the full term of its PTE."23

Thus, according to the Ezra court, the original expiration date of a patent (without PTE) should be considered as a reference point for determining if ODP applies.24 Because the '229 would expire before the '565 patent but for the PTE (i.e., the '229 patent was the earlier-expiring patent), the later-expiring '565 patent could not extend the exclusive rights to the invention of the '229 patent.25 Thus, the '565 patent was not an ODP reference to the '229 patent, and Novartis was not required to terminally disclaim any portion of the term of the '229 patent. The '229 patent was found to be not invalid and retained its full PTE term.

Despite the dicta from the Federal Circuit in AbbVie and the Michigan court's finding in Magna Electronics, patent practitioners can remain hopeful that the Federal Circuit would apply the ODP rule set forth in Ezra to patents that receive PTA. Indeed, it is not unreasonable to extend the reasoning in Ezra – judge-made ODP doctrine should not cut off statutorily authorized PTE – equally to PTA. While PTE is available for regulatory delays that limit a patentee's enjoyment of patent term, PTA is available for USPTO delays that likewise limit a patentee's enjoyment of patent term (in a post-URAA regime). For now, however, this remains an open question.

Difference in ODP analysis for pre- and post-URAA patents 

In Breckenridge, the Federal Circuit rejected the broad application of Gilead to pre-URAA patents and held that issue dates, rather than expiration dates, remain the proper basis for analyzing ODP of pre-URAA patents even when the reference patent is a post-URAA patent.26 At issue were two Novartis patents: US Patent Nos. 5,665,772 and 6,440,990.27 Although both patents claimed the same priority date (i.e., they belonged to the same chain of applications), the '990 patent was filed after the effective date of the URAA, and therefore expired 20 years from the earliest effective filing date, on 23 September 2013. The '772 patent, on the other hand, was filed before the effective date of the URAA and therefore was set to expire 17 years from its issuance, on 9 September 2014. Due to a five-year PTE, the '772 patent's term was extended to 9 September 2019. As shown below, the original term of the '772 patent encompasses that of the '990 patent even without considering the five-year term extension.28 

Applying Gilead, the district court found the '990 patent to be a proper double patenting reference for the '772 patent (noting a similar situation in Gilead but with two post-URAA patents).29 The Federal Circuit reversed and found that Gilead is not applicable to the facts of Breckenridge and Gilead's expiration date-based analysis cannot be applied across the board to pre-URAA patents.30 Distinguishing Gilead, where both the challenged and the reference patents were post-URAA patents, the Federal Circuit explained that Novartis's patents did not pose the problem of "unjustified time extension" or "patent prosecution gamesmanship" because the difference in expiration dates arose only because of an intervening change in law due to the implementation of the URAA.31 If both patents had been pre-URAA patents, the '990 patent would have expired on the same day as the '772 patent by operation of the terminal disclaimer that Novartis filed in the later-issued '990 patent.32 And if they had been both post-URAA patents, then they would have also both expired on the same day because they would have had the same effective filing date. 

The Breckenridge panel declined to invalidate the challenged pre-URAA patent based on a post-URAA reference patent.33 Instead, it applied the pre-Gilead issue date-based analysis to the challenged pre-URAA '772 patent and found that the post-URAA '990 patent is not a proper ODP reference. According to the panel, when the '772 patent issued, the '990 patent had not yet issued and thus did not exist as an ODP reference against the '772 patent, and that to find otherwise would "abrogate Novartis's right to enjoy one full patent term on its invention" prescribed by statute.34 

The decisions in Ezra and Breckenridge signal the Federal Circuit's willingness to limit the scope of Gilead and conduct a factual inquiry of whether the difference in expiration dates of the challenged and reference patents is due to patent prosecution gamesmanship, or due to statutorily granted patent terms (as in Ezra) or based on pre-URAA status (as in Breckenridge). Looking forward, the Federal Circuit may further rein in the broad reach of Gilead, limiting it to the facts of that case, i.e., two post-URAA patents having different priority dates and different expiration dates, and limiting the "judge-made doctrine" of ODP from cutting off statutorily increased patent terms. In the meantime, patent practitioners should consider the impacts of ODP during prosecution and after grant – portfolio and enforcement strategies may have unintended consequences. Stay tuned as we continue to follow this evolving area of US patent law. 


1 January-February [2017] CIPA 22

2 Gilead Sciences, Inc. v Natco Pharma Ltd., 753 F.3d 1208, 1215 (Fed. Cir. 2014)

3 Id. at 1212, 1217

4 See id.

5 Id. at 1215-16.

6 US patents issued from applications filed after the Uruguay Round Agreements Act (URAA), effective 8 June 1995, have a term

of 20 years measured from their earliest effective filing date. In contrast, the patents issued from applications filed before the

URAA have a term of 17 years from the issue date of the patent.

7 Novartis AG v Ezra Ventures LLC, 909 F.3d 1367 (Fed. Cir. 2018)

Novartis Pharmaceuticals Corp. v Breckenridge Pharmaceutical Inc., 909 F.3d 1355 (Fed. Cir. 2018)

9 Gilead, 753 F.3d at 1210.

10 Gilead, 753 F.3d at 1212, 1215, 1217.

11 No. 1:12-cv-654, 2015 WL 11430786, at *3 (W.D. Mich. Dec. 10, 2015)

12 Id. at **3-5.

13 See id. at *6.

14 On a separate note, terminal disclaimers can be fi led during prosecution (to overcome an ODP rejection) or anytime during the valid term of an issued patent, if the respective patents or patent applications are commonly owned. See, e.g., Boehringer

Ingelheim Int'l GmbH v Barr Labs., Inc., 592 F.3d 1340, 1347 (Fed. Cir. 2010) (citing cases).

15 764 F.3d 1366 (Fed. Cir. 2014), which discussed ODP and PTA in dicta. See Magna Electronics, 2015 WL 11430786, at *1.

16 Id. at 1370-72.

17 Of note, Judge Chen authored the majority opinion in Gilead and also authored the unanimous opinion in Ezra. Compare

Gilead, 753 F.3d at 1209 with Ezra, 909 F.3d at 1368. 

18 Ezra, 909 F.3d at 1369, 1373.

19 Id. at 1369-70.

20 Id. at 1370.

21 Under US law, a patentee can seek PTE for only one patent that covers a regulatory approved product, even though multiple

patents may qualify for extension. See, e.g., Ezra 909 F.3d at 1369. Thus, a patentee has wide latitude to choose which patent it will

extend. Id.

22 Ezra, 909 F.3d at Id. at 1373.

23 Id. at 1375.

24 See id.

25 See id. at 1374-75.

26 Breckenridge, 909 F.3d at 1366.

27 Id. at 1358, 1359.

28 Id. at 1359-60.

29 Id. at 1360.

30 Id. at 1358, 1364.

31 Id. at 1363, 1364.

32 Id. at 1364.

33 Id. at 1366.

34 Id. at 1366, 1367.

Originally published in CIPA Journal

The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.

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