Patent Trial and Appeal Board Finds Transitional Patent Eligible for PGR, Invalidates Claims, and Rejects Novel Argument That Bankruptcy Stay Ran out the PTAB Clock

November 22, 2021

The United States Patent and Trademark Office’s Patent Trial and Appeal Board (PTAB) has found all challenged claims (1–17) of Purdue’s U.S. Patent No. 9,693,961 (the ʼ961 patent) to be unpatentable. Robins Kaplan’s client, patent challenger Collegium Pharmaceutical, Inc., a specialty pharmaceutical company, maintained that the patent was invalid on multiple grounds. The PTAB’s final written decision confirmed that the ʼ961 patent was invalid for lack of written description and anticipation. The ʼ961 patent—the sixth Purdue patent to be found invalid or not infringed in ongoing litigation with Collegium—relates generally to controlled release oral dosage forms subject to less parenteral, intranasal, or oral abuse than other dosage forms.

The ʼ961 patent was first asserted against Collegium in 2017, when Purdue filed a patent infringement suit in the United States District Court for the District of Massachusetts. In March 2018, Collegium filed a Petition for Post-Grant Review (PGR) of the ʼ961 patent with the PTAB. In response, Purdue argued, among other claims, that the ʼ961 patent was not eligible for PGR due to the patent’s purported priority date. The PTAB disagreed and instituted? post-grant review of all claims in October 2018.

Days before the PTAB was set to issue its final written decision, Purdue filed for bankruptcy and later argued, due to the passage of more than eighteen months since institution of the PGR, that the bankruptcy divested the PTAB of its authority to issue a final written decision. The Board acknowledged the “unusual circumstances” presented by this PGR, as it had “not previously missed” its eighteen-month deadline to issue a final written decision. It nevertheless rejected Purdue’s argument and issued a decision invalidating the challenged claims of the ʼ961 patent.

“We feel the Board correctly determined that ‘the specification fails to reasonably convey that the inventors had possession of an abuse deterrent controlled release dosage form that included all the claimed pharmaceutical ingredients,’’’ says Robins Kaplan attorney Jake Holdreith. “In particular, the Board correctly held that the patent disclosure’s ‘laundry list of potential components’ did not adequately describe the claimed invention.”

Robins Kaplan attorney Christopher Pinahs adds, “We were pleased that the Board correctly concluded that the invalidated claims were directed to a pharmaceutical dosage form ‘not taught, described, or even forecast in the specification.’”

Collegium was represented in the PGR by Jake Holdreith, Chris Pinahs, Cy Morton, Oren Langer, Emily Tremblay and Alice Ribbens

Jake M. Holdreith


Managing Partner, Minneapolis Office
Member of Executive Board

Cyrus A. Morton


Chair, Patent Office Trials Group

Oren D. Langer


Managing Partner, New York Office

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