On March 11, 2026, the Director General of the Mexican Institute of Industrial Property (IMPI) published an amendment to Article 11 of the “Agreement Establishing the Response Times for Various Procedures before IMPI” in the Official Gazette of the Federation, which specifically governs the examination of patent applications.

Article 11 previously granted applicants the opportunity to receive as many as four office actions during the examination. This number has been reduced to a maximum of two office actions. The recently published amendment will have a significant impact on patent prosecution in Mexico.

It is this firm’s experience that only 15% to 25% of filed applications reach a third or fourth office action because of the restricted practice pertaining to divisional applications. Consequently, the impossibility of continuing the examination process, as well as the lack of admittance of post-grant or post-refusal changes to the claims, means any additional embodiments will need to be incorporated into the application as soon as possible, either before the issuance of the notice of allowance or the refusal of the application, as the case may be.