The Case for Using Filing Dates Instead of Expiration Dates to Determine Obviousness-Type Double Patenting (Part I)

“The best course of action would be to eliminate ODP altogether. However, to the extent that is not feasible, there is an easy solution that solves most of these problems and comports with historical ODP treatment.”

obviousness-type double patentingThe judicially-created doctrine of obviousness-type double patenting (ODP) originated long ago as a shield to protect the public against unwarranted patent term extension (PTE). The Uruguay Round Agreements Act of 1994 (URAA) removed most of these concerns when it changed statutory term from 17 years from issue to 20 years from earliest effective filing date. By limiting patent families to a single 20-year term, the URAA eliminated the ability of patent owners to indefinitely extend the term of their invention by filing successive continuations claiming similar subject matter. After the URAA, all patents in a family are effectively limited to the 20-year term of the first-filed patent, plus an occasional modest term extension due to regulatory delays (PTE) or delays at the U.S. Patent and Trademark Office (USPTO) (Patent Term Adjustment (PTA)). Thus, for post-URAA patents, the concern that led to the judicial creation of ODP is largely an historical artifact as most patent families share a single 20-year term and the ones that don’t have terms that vary by a few years at most.

Instead of limiting or eliminating the judicially-created doctrine of ODP, recent Federal Circuit decisions have actually expanded the doctrine. No longer is ODP used simply to ensure that later patents are not used to improperly extend the patent term for a first patent. Now, ODP may be used as a sword to retroactively invalidate patents prosecuted in good faith.

The basis for this expansion is the argument that the patent in a family with the earliest expiration date should be used as the starting point for the ODP analysis—that is, no patent in a family subject to ODP should have a later expiration date than the patent in the family that expires first. But a review of the caselaw indicates a dearth of historical support for this position. Further, because ODP is an historical artifact from a different statutory framework, this expansion in many cases results in inconsistent and potentially inequitable results.

The best course of action would be to eliminate ODP altogether. However, to the extent that is not feasible, there is an easy solution that solves most of these problems and comports with historical ODP treatment. Instead of using the patent with the earliest expiration date as the basis for ODP rejections, use the earliest filing date  in the family.

In re Cellect Creates ODP Minefield for Patent Owners

The Federal Circuit’s recent In re Cellect opinion illustrates the problems with the current ODP framework. Cellect held that the expiration date used for an ODP analysis where a patent has received PTA is the expiration date after the addition of the patent-term adjustment. In re Cellect, 81 F.4th 1216 (Fed. Cir. 2023). Moreover, the panel did not merely limit the term of the challenged patents to the term of the (expired) patent in the family with the shortest term, they were each retroactively invalidated. The patent in the family with the shortest term in the family had already expired, and the court reasoned that a retroactive terminal disclaimer could not be filed against a patent that had already expired. Cellect, 1231.

The implication of In re Cellect is not good for patent owners. An applicant files a patent application that, because of delays by the USPTO, results in two years of PTA and a term of 22 years from filing of the original application. After filing the original application, the applicant files a continuation off the original application that is issued in due course with a normal term (i.e., 20 years from the filing of the original application). Thus, the continuation patent expires two years before the parent patent. Ordinarily, the applicant would not file a terminal disclaimer during prosecution of the first-filed application because there is nothing to disclaim against.

Fast forward 20 years, and the original, first-filed patent is in litigation. The defendant can file a reexamination based on ODP to attempt to force the patent owner to disclaim the duly-granted PTA on the earlier-filed original patent based on the later-filed patent. Further, if the defendant waits to file the reexamination until after the later (second-filed) patent expires, under In re Cellect, the patent owner can no longer file a terminal disclaimer because the second patent is expired. The original patent does not simply retroactively lose the portion of its term granted through PTA; the original patent is completely invalidated and any past damages are gone.

This is an inequitable result for patent owners. The patent owner has likely spent millions of dollars over several decades prosecuting and litigating a patent portfolio in good faith. The patent owner had no reason to suspect that duly granted PTA could be retroactively revoked, or that its patents are retroactively invalidated over a later-filed patent because the patent owner did not file a terminal disclaimer it had no reason to suspect needed to be filed.

Why Does the Federal Circuit Use Expiration Dates for ODP Analyses in the First Place?

The In re Cellect opinion assumes that ODP should always be based on the patent in a family with the earliest expiration date. That assumption traces back through Novartis Pharms. v. Breckenridge Pharm., 909 F.3d 1355, 1360, (Fed. Cir. 2018) (“Novartis I”) and Novartis AG v. Ezra Ventures LLC, 909 F.3d 1367 (Fed. Cir. 2018) (“Novartis II”) to Gilead Sciences, Inc. v. Natco Pharma Ltd., 753 F.3d 1208, 1217 (Fed. Cir. 2014). Both Novartis opinions cite Gilead for its discussion on ODP and all three were authored by Judge Chen.

Collectively, these decisions have been interpreted to stand for the proposition that the ODP analysis should be based on the earliest-expiring patent in a family. See, e.g., MPEP 804; Cellect, 1227. A closer reading of these three decisions suggests that these opinions did not intend the proposition to be as absolute as implied in Cellect. Further, Gilead’s initial focus on patent expiration date as the critical date for ODP analyses—rather than eliminating the practice in light of the URAA or using the earliest filing date—provides little legal support for doing so.

In Part II of this article, we will look at how the case law around ODP has developed, where it went wrong, and how the Federal Circuit could get us back on track.


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Author: lightsource
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  • [Avatar for Pro Say]
    Pro Say
    May 6, 2024 02:12 pm

    “This is an inequitable result for patent owners.”

    If only the CAFC gave a d.a.m.n.

    If only.

    Congress: Dissolve this off-the-legal-rails, shameful embarrassment to America’s judiciary. It no longer serves the purpose for which it was created.

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