CAFC Says University of Minnesota Patent Fails Written Description Test

“The listings of possibilities are so long, and so interwoven, that it is quite unclear how many compounds actually fall within the described genera and subgenera.” – CAFC

written descriptionIn a precedential decision published Monday, the United States Court of Appeals for the Federal Circuit (CAFC) affirmed the Patent Trial and Appeal Board’s (PTAB) decision to invalidate a pharmaceutical patent owned by the University of Minnesota.

Gilead Sciences filed an inter partes review (IPR) in 2017 challenging the claims of the university’s  U.S. Patent 8,815,830 as unpatentable. The ‘830 patent covers chemical compounds that prevent the reproduction of viruses or the growth of cancerous tumors.

The PTAB found that the University of Minnesota failed to provide a sufficient written description that supported the patent’s priority claim. The Board thus concluded that the patent would not guide a skilled artisan to the patent’s claims.

The CAFC agreed with the PTAB’s decision and with the ruling that a 2010 patent application publication filed by Gilead was “prior art” over the university’s patent. The CAFC also ruled that the university was collaterally estopped from making the argument that the university is a sovereign state entity after  the Supreme Court declined to hear the argument in a previous case.

Issue at Hand

According to the circuit judges, the written description requirement “raises particular issues” in this case because the patent claims a genus of chemical compounds. This is because a broad outline of the genus is insufficient and the patent owner must also describe “the outer limits of the genus but also of either a representative number of members of the genus or structural features common to the members of the genus.”

Gilead has an Food and Drug Administration (FDA)-approved drug, sofosbuvir, that falls under the genus of a claim in the ’830 patent. The pharmaceutical company markets the drug as treating chronic hepatitis C infections. Gilead argued that one of its patent applications from 2010 anticipated the ‘830 patent.

Rather than claiming that the patent sufficiently described the claimed subgenus, the University of Minnesota argued that the Board erred when it ruled that two prior patent applications do not contain a sufficient written description. The PTAB and the CAFC both disagreed with this claim.

A ‘Maze-Like Path’

According to the circuit court judges, the university’s arguments form a “maze-like path, each step providing multiple alternative paths” rather than a “written description of what might have been described if each of the optional steps had been set forth as the only option.”

The circuit judges thus quoted the famous baseball player Yogi Berra, known for his aphorisms, who said, “when one comes to a fork in the road, take it.”

“The listings of possibilities are so long, and so interwoven, that it is quite unclear how many compounds actually fall within the described genera and subgenera,” wrote the judges.

Similarly, the PTAB ruled that the university failed to provide sufficient blaze marks to support the patent priority claims. Again, the CAFC agreed with the Board’s ruling. Here the CAFC cited Fujikawa v. Wattanasin and wrote, “the priority applications “do[] not direct one to the proposed tree in particular, and do[] not teach the point at which one should leave the trail to find it.”

The CAFC also agreed with the Board, that the University of Minnesota mischaracterized the standard in Ariad Pharms., Inc. v. Eli Lilly & Co. by claiming that disclosure of structural features was sufficient to show possession of the claimed genus. The Ariad case sets out two additional requirements, the first of which the University of Minnesota agreed it had not met.

The second requirement is a disclosure of “structural features common to the members of the genus.” However, the PTAB ruled that there was insufficient evidence of blaze marks, which the CAFC ruled was “not error.”

According to the court, these common structural features must constitute the near-entirety of the structures being compared. But, “the structures here are so extensive and varied that the structures of [the first patent’s] claim 47, which, through its multiple dependencies, encompasses a significantly larger genus than that claimed in the ’830 patent, are not sufficiently common to that of claim 1 of the ’830 patent to provide written description support,” wrote the circuit court judges.

Ultimately, because the Board and CAFC found no adequate blaze marks in the priority patent applications, Gilead’s 2010 patent application is considered prior art to the patent, said the court.

Alleged APA Violations and Collateral Estoppel

The University of Minnesota also claimed that the PTAB “ran afoul” of several requirements of the Administrative Procedure Act (APA).

First, the university argued that the Board failed to address aspects of their expert witnesses’ testimony. However, the CAFC cited precedent that states that “the Board is not required to address every argument raised by a party or explain every possible reason supporting its conclusion.”

Secondly, the patent owners attempted to cite a previous non-precedential written decision from the PTAB that the university argued was inconsistent with the PTAB’s ruling in the case. However, the Board and the CAFC ruled that the case is significantly different from the University of Minnesota’s case. The CAFC also found no other APA violations outlined by the university.

Finally, the university argued that it is a sovereign state entity immune from IPR. However, the CAFC previously rejected this argument from the University of Minnesota and the Supreme Court declined to hear the case.

“Because this issue has been litigated to finality and determined on the merits, Minnesota is collaterally estopped from making an immunity argument here,” ruled the CAFC.

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Author: Alexis84


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