By: Jinming Zhang

On February 22, 2021, a panel majority of the Court of Appeal for the Federal Circuit determined, in SynQor, Inc v. Vicor Corp., No. 2019-1704, that issue preclusion can apply to previous inter parte reexamination decisions. Judge Dyk strongly dissented. 

In 2011, SynQor, Inc. asserted multiple patents against Vicor Corp in a district court litigation, including U.S. Patent Nos. 7,702,190 (“the ’190 Patent”), 7,564,702 (“the ’702 Patent”), and 8,023,290 (“the ’290 Patent”). The three patents are parts of an extensive patent family based on parent applications dating back to 1997. The patents all disclose “technology for DC-DC power converters used in large computer systems, and telecommunication and data communication equipment to convert direct electric current from one voltage to another.” Vicor Corp subsequently petitioned for inter parte reexamination of the ’190, the ’702, and the ’290 patents arguing that the claims of these patents are obvious in view of two references: (1) U.S. Patent No. 5,377,090 (“Steigerwald”) and published article “Cobos.” 

On appeal from the ’702 and ’290 patents reexaminations, the PTAB affirmed that the challenged claims were not invalid because “there are incompatibilities in frequency” between the references, Steigerwald and Cobos. Thus, a person of skill in the art would not have been motivated to combine the two references. The Federal Circuit later affirmed this decision after the parties appealed. 

In the proceedings for the ’190 patent, however, the Board contradicted its prior decision regarding the ’702 and ’290 patents and found the references, Steigerwald and Cobos, did not disclose incompatible frequencies and that the challenged claims were therefore unpatentable. SynQor, Inc. appealed the Board’s decision regarding the ’190 patent and argued that issue preclusion arising from the ’702 and ’290 patent reexaminations should have collaterally estopped the Board from reaching the opposite decision when interpreting the references. 

The Federal Circuit panel majority agreed with SynQor, Inc., and determined that common law issue preclusion can apply to prior inter parte reexamination decisions. The majority first determined that the statutory scheme governing the reexamination proceeding showed no evidence of Congress’s intent to foreclose common law issue preclusion. The panel then determined that although the reexamination proceedings are not formally adversarial as IPR proceedings, it nevertheless provides “adequate adversarial participation for both the patent owner and requester” as both parties can present and rebut evidence. The panel also rejected Vicor Corp’s argument that the lack of cross-examinations and “compulsory process,” such as subpoenas, makes reexamination proceedings merely “inquisitory” in nature and should not have issue preclusive effect. The panel stated that neither compulsory process nor cross-examination is dispositive in determining the preclusive effect of an administrative decision. The panel determined that because the reexamination proceedings provide a full and fair opportunity to litigate to both parties, issue preclusion can apply. 

Having determined that issue preclusion can apply to reexamination proceedings, the panel majority held that the ’702 and ’290 patent reexamination proceedings precluded the Board from reaching its opposite decision in the ’190 patent reexamination. The panel first stated that issue preclusion can apply to different claims so long as the same issue was litigated and determined. In this case, the only issue essential to the Board’s decision was whether Cobos and Steigerwald disclosed mutually incompatible frequencies. The panel determined that the issue was litigated and determined in both the ’290 and ’702 patent reexaminations. Thus, the panel held that the Board was precluded from reaching its contrary decision in the ’190 patent reexamination even if Vicor Corp introduced new evidence. 

The Federal Circuit’s decision, in this case, should raise several red flags for parties potentially litigating pre-AIA patents. First, because of the preclusive effect of reexamination, the parties should be careful in managing their litigation strategies before the Office and the Board to prevent unintended issue preclusion effects. Additionally, this case shows that reexamination proceedings of patent families can have a preclusive effect on different patents in the family when the same issues were litigated and decided in prior reexaminations. Both patentees and potential infringers should be cognizant of this far-reaching effect of reexamination proceedings and prepare their litigation strategy accordingly.

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Tom Dunlap is a partner at Dunlap Bennett & Ludwig. Tom’s practice focuses on patent, trademark, trade secret, commercial, entertainment law, business, government contracts disputes, litigation, and transactions. Tom has authored numerous books and appeared on national television and radio, including Fox, Sundance T.V., and NPR, speaking on various subjects in his fields of practice. In addition to the state and federal courts of D.C., VA, and M.D., he is a member of the Federal Courts in Puerto Rico, Colorado, and Texas, as well as the Court of Federal Claims, the Federal Circuit, where he has recently argued and won three appellate matters, the Veteran’s Court of Appeals, and the United States Supreme Court, where he was lead counsel on a False Claims Act case (See United States ex rel. Carter v. Halliburton Co.) and in the T.C. Heartland LLC v. Kraft Foods Group Brands LLC (U.S. May 22, 2017) (No. 16-341) case involving jurisdiction in patent infringement cases. Other recent litigation victories where Tom served as lead trial counsel include a $12,317,500 verdict in Zuru v Telebrands et al. (EDTX 2017) (patent infringement) and a $2,600,000 verdict in DPX Gear v Prince et al. (Loudoun Circuit Court 2017) (breach of contract & fraud).

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