Athena Automation IPR decision rejecting equitable defense of assignor estoppel in IPR proceedings designated precedential by the PTAB

On August 2, 2017, the Patent Trial and Appeal Board (PTAB) designated Section II.A. of the Institution Decision in Athena Automation Ltd. v. Husky Injection Molding Systems Ltd., IPR2013-00290, Paper 18 (PTAB Oct. 25, 2013) as precedential. The designated portion of this case finds that the doctrine of assignor estoppel does not apply to inter partes review proceedings. This is only the 10th AIA post-grant proceeding identified as precedential.

The IPR2013-00290 IPR proceeding ('290 IPR) stems from one of three petitions filed by Athena Automation against three different patents held by Husky Injection Molding Systems, related to injection molding machines that inject, under pressure, injectable molding material into a mold cavity. The '290 IPR Petition challenged all 22 claims of U.S. Patent No. 7,670,536 based on six distinct grounds. The Board instituted review on three of the proposed grounds.

The portion of the institution decision designated as precedential (Section II.A.) addresses arguments made by Husky in the Preliminary Response relating to the doctrine of assignor estoppel. The Federal Circuit has described the doctrine of assignor estoppel as such:

[A]ssignor estoppel is an equitable doctrine that prohibits an assignor of a patent or patent application, or one in privity with him, from attacking the validity of that patent when he is sued for infringement by the assignee. . . . Assignor estoppel is thus a defense to certain claims of patent infringement.

Semiconductor Energy Laboratory Co., Ltd. v. Nagata, 706 F.3d 1365, 1369 (Fed. Cir. 2013) (citations omitted).

The Board held that assignor estoppel does not apply to IPR due to the broadly inclusive language of 35 U.S.C. 311(a), which states that under the AIA "a person who is not the owner of a patent may file with the Office a petition to institute an inter partes review of the patent" (emphasis added). The Board then addressed the differing standards of the International Trade Commission (ITC) and the PTAB, pointing out that Congress provided explicitly that for ITC proceedings "[a]ll legal and equitable defenses may be presented in all cases" yet did not issue a similar statutory mandate with respect to AIA post-grant proceedings.

While the Board's decision in Athena Automation identifies "inter partes review" proceedings in particular when declining to apply the equitable doctrine of assignor estoppel, the Board did point out that Congress has issued no statutory mandate requiring availability of "equitable defenses" for any of the "AIA post-grant reviews." Therefore, it appears that this precedential decision applies equally to CBM and PGR proceedings.