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On September 16, 2025, the Acting Director of the US Patent and Trademark Office (USPTO) issued another memorandum outlining new guidance for patent claims challenged before the Patent Trial and Appeal Board (PTAB). This guidance applies when the PTAB is reviewing patent claims (or substantially similar patent claims) that have already been adjudicated in a federal district court, the US International Trade Commission (ITC), or in a previous USPTO proceeding.
Key Takeaways
- Duty to Explain: If the Board reaches a finding of fact or conclusion of law that is different from a prior ruling on the same or similar claims, it is now required to provide a detailed written explanation for the different outcome. This explanation must be articulated in its institution decision or final written decision.
- Heightened Standard: A "more detailed explanation" is required from the Board if the evidence and arguments being presented are the same or substantially the same as those in the prior proceeding.
- Procedural Impact: The Board will consider relevant materials from the other proceeding (like opinions, judgments, or testimony) and may allow for additional briefing on the issue.
- Application: The memo applies to situations where the Board reaches an initial or final decision on a finding of fact or conclusion of law.
Strategic Considerations for Practitioners
- For Patent Owners: This memo provides a new tool to leverage favorable prior rulings regarding the validity of its patents. These should be submitted to the Board to argue for deference or require the Board to provide a more detailed explanation for the different outcome.
- For Petitioners: This memo creates a new hurdle when challenging claims that were found valid in a prior proceeding. To succeed, a petition should proactively:
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- Differentiate Your Case: Introduce new evidence, new prior art or make fundamentally different legal arguments.
- Justify a Different Outcome: Clearly explain why the PTAB should reach a conclusion different from the previous court or agency by providing the PTAB with enough evidence and explanation to support their opinion that a different outcome is warranted.
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