Title 35 › Part III— PATENTS AND PROTECTION OF PATENT RIGHTS › Chapter 32— POST-GRANT REVIEW › § 325
A post-grant review cannot start if the person who asked for it, or someone on their side, already sued in court to challenge the same patent before filing the review. If the court case is filed after the review petition, that court case is automatically paused until the patent owner asks to lift the pause, the patent owner files a suit or counterclaim saying the petitioner infringed, or the petitioner asks the court to dismiss the case. A counterclaim does not count as starting a separate court challenge. If an infringement suit is filed within 3 months after the patent is granted, a court may not delay deciding a patent owner’s request for a temporary injunction just because a post-grant review was filed or begun. If more than one valid petition is filed against the same patent and the Patent Office decides more than one should go forward, the Director may merge them into one review. While a post-grant review is going on, the Director can decide how other Office proceedings about the same patent proceed, including pausing, moving, combining, or ending them, and may refuse to start a new Office proceeding if the same or basically the same prior art or arguments were already shown. If a post-grant review ends with a final written decision, the petitioner and people closely related to them cannot later challenge that claim before the Office, in federal court, or at the International Trade Commission on any ground they raised or could have raised in the review. A review also cannot start if it asks to cancel a claim in a reissue patent that is identical to or narrower than an original claim and the time limit in the rules would have barred a review of the original patent.
Full Legal Text
Patents — Source: USLM XML via OLRC
Legislative History
Reference
Citation
35 U.S.C. § 325
Title 35 — Patents
Last Updated
Apr 5, 2026
Release point: 119-73not60