Title 35 › Part PART III— - PATENTS AND PROTECTION OF PATENT RIGHTS › Chapter CHAPTER 25— - AMENDMENT AND CORRECTION OF PATENTS › § 252
When a patent is reissued, the original patent is given up as soon as the corrected patent is issued. The reissued patent works the same in future lawsuits as if it had been granted in that corrected form from the start. If the reissued claims are basically the same as the original claims, giving up the original does not stop any lawsuit already started, and the reissued patent keeps the original patent’s effective date. People who, before the reissue, made, bought, offered, used, or imported the specific patented thing in the U.S. may keep making, using, or selling that same thing unless it violates a valid claim that was in the original patent. A court can allow continued manufacture, sale, use, or practice of a process when substantial steps were taken before the reissue and can set fair terms to protect prior investments or businesses.
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Patents — Source: USLM XML via OLRC
Legislative History
Reference
Citation
35 U.S.C. § 252
Title 35 — Patents
Last Updated
Apr 6, 2026
Release point: 119-73