Can a later-granted patent render an earlier-granted patent invalid for obviousness-type double patenting? In Gilead Sciences, Inc. v. Natco Pharma Limited, the Federal Circuit held that it can. This decision could have far-reaching impact on the ability of patent owners to fully protect their inventions or enjoy the full benefit of patent term adjustment awards.
The Patents at Issue
The patents at issue were Gilead's U.S. Patent Nos. 5,763,483 and 5,952,375, which are directed to antiviral compounds and methods using them. As noted by the Federal Circuit, "[w]hile the patents list the same inventors and the written descriptions disclose similar content, they do not claim priority to a common patent application and have different expiration dates." While not discussed by the court, the '375 patent appears to clam a genus of compounds, while the '483 patent appears to claim two specific compounds and methods of using them.
The Federal Circuit decision includes this chart of the relative filing, issue and expiration dates of the patents:
A Terminal Disclaimer was filed in the '375 patent over the '483 patent, but not vice versa.
The District Court Proceedings
The district court litigation arose from Natco's Abbreviated New Drug Application (ANDA) seeking FDA approval to market a generic version of a Gilead drug covered by the '483 patent.
Before the district court, Natco argued that the '483 patent was invalid for obviousness-type double patenting over the '375 patent. Gilead argued that the '375 patent could not be cited against the '483 patent because the '375 patent issued later, and the district court agreed.
The Federal Circuit Decision
The Federal Circuit decision was authored by Judge Chen and joined by Judge Prost. Chief Judge Rader wrote a dissenting opinion.
Judge Chen framed the issue before the court as follows:
Can a patent that issues after but expires before another patent qualify as a double patenting reference for that other patent?
Judge Chen traces the doctrine against double patenting as being "based on the core principle that, in exchange for a patent, an inventor must fully disclose his invention and promise to permit free use of it at the end of his patent term." Judge Chen also notes that the doctrine has been used "to preserve the public's right to use not only the exact invention claimed by an inventor when his patent expires, but also obvious modifications of that invention that are not patentably distinct improvements."
Judge Chen begins his analysis of the case at hand with this telling statement:
[I]t is a bedrock principle of our patent system that when a patent expires, the public is free to use not only the same invention claimed in the expired patent but also obvious or patentably indistinct modifications of that invention.
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And that principle is violated when a patent expires and the public is nevertheless barred from practicing obvious modifications of the invention claimed in that patent because the inventor holds another later-expiring patent with claims for obvious modifications of the invention. Such is the case here.
Judge Chen (and Judge Prost) rejected Gilead's argument that relative issue dates determine whether one patent can be cited against another in a double-patenting rejection, and determined instead that it is the relative expiration dates that are controlling:
Looking ... to the earliest expiration date of all the patents an inventor has on his invention and its obvious variants best fits and serves the purpose of the doctrine of double patenting. Permitting any earlier expiring patent to serve as a double patenting reference for a patent subject to the URAA guarantees a stable benchmark that preserves the public's right to use the invention (and its obvious variants) that are claimed in a patent when that patent expires.
The majority noted that this approach "preserves the ability of inventors to use a terminal disclaimer of later-expiring patents to create one expiration date for their term of exclusivity over their inventions and obvious variants."
Having decided that the district court had erred in determining that the '375 patent could not qualify as a double-patenting reference against the '483 patent, the Federal Circuit vacated the district court decision and remanded for further proceedings.
Chief Judge Rader's Dissent
Chief Judge Rader dissented from the majority decision to express his views that its "expansion" of the doctrine of obviousness-type double patenting was "unwarranted."
Chief Judge Rader notes two traditional justifications for the doctrine, and finds that neither are applicable here.
- The need to curtail the practice possible under the pre-GATT,
17-year patent term regime, of filing "successive
continuations and obtain[ing] additional patent term for obvious
modifications of ... earlier claims where ... earlier patents and
applications did not qualify as prior art."
Here, the patent held invalid–the later-filed '483 patent–did not extend the term of the earlier filed '375 patent. - The need to "prevent[] multiple infringement suits by
different assignees asserting essentially the same patented
invention.
Here, the two patents are commonly owned.
Chief Judge Rader also drew a line between same invention-type double patenting and obviousness-type double patenting:
I differ with the court on the effect this court should give to subsequent attempts by a patent owner to seek exclusive rights to obvious variants that do not extend the term of its earlier patent. Because this court is not presented with same-invention double patenting, I am aware of no argument that the Patent Act precludes such conduct. And because the patents in this case are subject to a common ownership requirement, that concern provides no basis for complaining of Gilead's conduct.
Overall, Chief Judge Rader expresses regret that the majority did not approach this issue with more judicial restraint.
The Obviousness-Type Double Patenting Morass
Like Chief Judge Rader, I wish the Federal Circuit had approached this issue with more restraint, as this case could have far-reaching implications that the court may not have considered. For example, in the case of serial continuation applications, where the first patent is granted with a substantial amount of patent term adjustment for USPTO examination delays, must the patent owner now disclaim that term if it subsequently obtains a patent to an "obvious variant" (such as a genus of the first patented species, or a species beloning to the same genus of the first patented species)?
I hope you will join me and Kimberly Prior, Senior Patent Counsel at Johnson & Johnson, as we make our way through these and other issues during the AIPLA Webinar on obviousness-type double patenting scheduled for May 8, 2014 at 12:30 Eastern. (You can register here).
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.
