Can a patent owner amend claims after an Action Closing Prosecution (ACP)?

This page is an FAQ based on guidance from the Manual of Patent Examining Procedure. It is provided as guidance, with links to the ground truth sources. This is information only: it is not legal advice.

According to MPEP 2673, a patent owner cannot, as a matter of right, amend claims rejected in the ACP, add new claims after an ACP, or reinstate previously canceled claims. The MPEP states:

“A showing under 37 CFR 1.116(b) is required and will be evaluated by the examiner for all proposed amendments after the ACP, except where an amendment merely cancels claims, adopts examiner’s suggestions, removes issues for appeal, or in some other way requires only a cursory review by the examiner.”

This means that while amendments are not automatically allowed after an ACP, they may be considered if they meet certain criteria or if they simplify the issues at hand.