What happens if a patent is determined to be ineligible for extension after an interim extension has been granted?

If a patent is determined to be ineligible for extension after an interim extension has been granted, the interim extension may be revoked. According to MPEP 2755.01:

Where an interim extension has been granted and it is subsequently determined that the patent is not eligible for patent term extension, the interim extension may be vacated ab initio as ineligible under 35 U.S.C. 156(e)(2).

The MPEP cites the case of In re Reckitt, 230 USPQ at 370, as a precedent for this action. This means that if a patent is found to be ineligible for extension, any interim extension that was granted can be retroactively cancelled, as if it had never been granted in the first place.

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Topics: Adjustments, And Extensions, MPEP 2700 - Patent Terms, MPEP 2755.01 - Interim Extension Of Patent Term During The Processing Of The Application, Patent Law, Patent Procedure
Tags: Interim Extension, Patent Ineligibility, patent term, USPTO