PTAB Shakeup: Stewart's Discretionary Denials Reshape Patent Battles

In March 2025, Stewart issued a memo introducing a new discretionary denial framework. Her approach bifurcates the process—first allowing the Director to assess whether a case should be reviewed on procedural or equitable grounds, and only then permitting the PTAB to evaluate the merits of the patent challenge. While that sounds bureaucratic, the real-world impact is profound.

One of the most consequential shifts comes with the introduction of a new factor called “settled expectations.” This concept essentially considers how long a patent has been in force and how reliant industries or businesses may have become on its validity. If a patent has been unchallenged and commercially active for years, Stewart’s office may consider that reason enough to deny an IPR petition — even before its merits are heard.

For instance, in iRhythm v. Welch Allyn, a key decision cited Stewart’s use of this “settled expectations” factor. The patent at issue was originally filed in 2012, and the Director found that overturning such a long-standing patent would unfairly disrupt market stability. The denial made no mention of the technical merits of the challenge — it was purely based on the timing and commercial reliance.

Other decisions — including Intel v. Proxense and Dabico v. AXA Powers — have followed the same logic. The new approach contrasts sharply with the former Fintiv framework, which emphasized factors such as parallel district court litigation and judicial efficiency. Stewart’s method shifts the focus to equity and fairness, particularly the perceived burden on patent owners of defending aged and relied-upon patents.

Critics of this new policy argue that it could chill legitimate challenges to weak patents, especially if potential challengers wait too long. On the flip side, proponents say it protects innovation investments and discourages strategic “wait-and-pounce” behavior where challengers delay filing IPRs until a patent becomes profitable — only to then try to invalidate it.

Patent owners, especially in sectors like pharmaceuticals, medical devices, and electronics, may view Stewart’s denials as a major win. It provides an added layer of protection against late-stage legal challenges. But petitioners — often large tech companies or competitors — may find themselves reassessing the timing and urgency of filing IPRs.