No blanket prohibition against the introduction of new evidence during an inter partes review

Federal CircuitThe Federal Circuit affirmed a decision of the Patent Trial and Appeal Board (PTAB) in an inter partes review (IPR) proceeding brought by the Coalition for Affordable Drugs X LLC holding that a patent owned by Anacor Pharmaceuticals was unpatentable due to obviousness. Anacor’s patent is directed to the use of a chemical compound, tavaborole, to treat fungal infections that occur under fingernails and toenails. The Board found that one claim of the patent is obvious in light of two prior art references. See Anacor Pharm., Inc. v. Iancu,No. 2017-1947, 2018 (Fed. Cir. May 14, 2018) (Before Reyna, Bryson, and Stoll, J.) (Opinion for the court, Bryson, J.).

The Court held that the Board did not violate due process and the procedural requirements of the Administrative Procedure Act (APA) that require adequate notice of, and an opportunity to respond to, the grounds of rejection determined by the Board.

Anacor argued that the Board changed its theory of invalidity by ultimately relying on a different combination of prior art references without providing Anacor proper notice or an opportunity to respond. However, the Board’s final written decision explicitly stated that its conclusion of obviousness was founded upon the same combination of two prior art references and same set of inferences as proposed in the petition by the Coalition.

Additionally, the Court determined that it was appropriate for the petitioner to rely on new evidence from references not included in the initial petition, to support its burden of showing a prima facie case of obviousness. There is no blanket prohibition against the introduction of new evidence during an inter partes review proceeding, indeed new evidence should be expected.  A petitioner can introduce new evidence following the petition, if it is a legitimate reply to evidence introduced by the patent owner, or if the new evidence is used to show the level of knowledge skilled artisans possess when reading the prior art references identified as grounds for obviousness. Here, the new evidence was properly offered to show the state of the art at the time of the patent application at issue. Furthermore, Anacor was given sufficient notice and an opportunity to respond. Thus, the Board did not violate due process or the procedural requirements of the Administrative Procedure Act.

Regarding obviousness, the Court held that the Board did not disregard the structural differences between the chemical compounds disclosed in the prior art references or improperly combine the references based on the similar functions of the chemical compounds disclosed. Anacor failed to cite any precedent holding that obviousness of a method of using a chemical compound can only be based on structural similarity to prior art compounds. Thus, despite some structural differences, it was proper for the Board to rely on the substantial functional similarities between the compounds in the prior art references, to conclude a person of ordinary skill in the art would have been motivated to combine them.

Finally, the Court determined that the Board did not improperly shift the burden of proof by requiring the patent owner, Anacor, to disprove obviousness. There was no evidence in the Board’s final written decision to suggest that it shifted the burden to Anacor. Rather, the Board explicitly stated that it was the petitioner’s burden to show unpatentability by a preponderance of evidence.

Take Away

It is permissible for a petitioner in an inter partes review proceeding to introduce new evidence, not in the initial petition, if the new evidence is in response to evidence introduced by the patent owner or documents the knowledge that skilled artisans would bring to bear in reading the prior art identified as grounds for obviousness. The opposing party must be given adequate notice of the new evidence and an opportunity to respond.  Although structural similarity between chemical compounds is a strong indicator of a motivation to combine and reasonable expectation of success, other arguments may support obviousness, case by case, such as functionally similar properties.

About Troutman Sanders and the Federal Circuit Review

Founded in 1897, Troutman Sanders LLP is an international law firm with more than 650 lawyers practicing in 16 offices located throughout the United States and Asia. Each week, partners Joe Robinson and Bob Schaffer, succinctly summarize the preceding week of Federal Circuit precedential patent opinions. They provide the pertinent facts, issues, and holdings. This Review allows you to keep abreast of the Federal Circuit’s activities – important for everyone concerned with intellectual property. is pleased to publish these summaries each week.

The Author

Robert Schaffer

Robert Schaffer is an intellectual property partner at Troutman Sanders. Bob applies more than 30 years of experience to IP counseling and litigation. His work includes patent procurement, strategic planning and transactional advice, due diligence investigations, district court patent cases, and Federal Circuit appeals. He regularly handles complex and high-profile domestic and international patent portfolios, intellectual property agreements and licensing, IP evaluations for collaborations, mergers, and acquisitions. In disputed court cases Bob’s work includes representing and counseling client in ANDA litigations, complex patent infringement cases and appeals, and multidistrict and international cases. In disputed Patent Office matters his work includes representing and counseling clients in interferences, reexaminations, reissues, post-grant proceedings, and in European Oppositions. For more information and to contact Bob please visit his profile page at the Troutman Sanders website.

Robert Schaffer

Joseph Robinson has over 20 years of experience in all aspects of intellectual property law. He focuses his practice in the pharmaceutical, life sciences, biotechnology, and medical device fields. His practice encompasses litigation, including Hatch-Waxman litigation; licensing; counseling; due diligence; and patent and trademark prosecution. He has served as litigation counsel in a variety of patent and trademark disputes in many different jurisdictions, and has also served as appellate counsel before the Court of Appeals for the Federal Circuit. Joe also focuses on complex inter partes matters before the U.S Patent and Trademark Office, inventorship disputes, reexaminations and reissues. His experience includes numerous interferences, a particular advantage in new U.S. Patent and Trademark Office post-grant proceedings. He also counsels on patent–related U.S. Food and Drug Administration issues, including citizen petitions, Orange Book listing, and trademark issues. For more information and to contact Joe please visit his profile page at the Troutman Sanders website.

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