Dickinson Wright is pleased to announce that the U.S. Court of Appeals for the Federal Circuit recently ruled in favor of the Firm's client, Inland Diamond Products Co., to vacate a district court's summary judgment and remand the case back to trial. The opinion (Inland Diamond Products Co. v. Cherry Optical Inc. (2025)) issued on October 15, is a precedential opinion that shapes and clarifies aspects of patent law as related to collateral estoppel.
"We are thrilled with the Court's decision in favor of our client," said Mark Jotanovic, lead counsel who argued the case in front of the U.S. Court of Appeals for the Federal Circuit. "The court rightly reversed the district court's decision and we look forward to the opportunity to argue our client's case based on evidence presented in court."
In 2020, Inland Diamond Products filed a case against Cherry Optical Inc. alleging that the defendant had infringed Asserted Claims of '360 and '130 patents. The United States District Court for the Eastern District of Wisconsin granted summary judgment in favor of Cherry Optical that the Asserted Claims were invalid for obviousness based on the doctrine of collateral estoppel stemming from Inter Partes Reviews (IPRs) decisions. Inland Diamond Products appealed the decision.
In their precedential opinion, the Federal Circuit decided that while issue preclusion, or collateral estoppel, prevents parties from litigating issues that were already decided, in the patent context it generally doesn't apply between Inter Partes Review (IPR) proceedings and later district court litigation. The key reason is that IPRs use a lower "preponderance of the evidence" standard to determine whether claims are unpatentable, while district courts require the higher "clear and convincing" standard to find a patent invalid. Because the factual issues in each setting are decided under different burdens of proof, the Federal Circuit held that PTAB fact-findings — like whether prior art teaches certain claim elements — cannot bind a district court. The Federal Circuit further stated that to grant summary judgment that an Asserted Claim is invalid for anticipation or obviousness, it must conclude on the basis of factual evidence and argument presented in court rather than issue preclusion stemming from the IPRs. Thus, factors like the prior art combination presented and claim construction orders between the PTAB and district court may create different factual records between each proceeding.
"Inland notes that this limitation applies mainly to factual findings, not necessarily to pure questions of law such as claim construction, which could have preclusive effect if the same legal standard (nowPhillipsin both forums) applies," said Mark. "Overall, the decision reaffirms that factual findings from IPRs don't carry over to court, but leaves open the possibility that some purely legal determinations might have that effect."
Inland Diamond Products Co. was represented by lead counsel Mark Jotanovic (Member, Troy). The team also included John S. Artz (Member and Intellectual Property Litigation Practice Group Chair Co-Chair, Ann Arbor) and Jonathan Nikkila (Member, Ann Arbor).