As the Patent Trial and Appeal Board access narrows and institution denials surge, accused infringers are rapidly pivoting to ex parte re-examination as their primary validity tool at the United States Patent and Trademark Office.
In 2025, PTAB institution rates dropped sharply following director-driven denials and proposed categorical inter partes review bars. At the same time, re-exam filings surged more than 66% year over year, reaching record highs. With its lower institution threshold, flexible timing and minimal estoppel exposure, the re-exam has emerged as the most predictable USPTO validity pathway.
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