Mexico's Patent Office Includes Second-Use Pharmaceutical Patents in Linkage Gazette for First Time
Key Insights
The Mexican Institute of Industrial Property (search) (IMPI (search)) published an atypical October 2025 edition of its Linkage Gazette, marking the first inclusion of second-use pharmaceutical patents after over two decades of exclusion.
This policy shift follows pressure from the United States under the USMCA review process and multiple amparo court rulings that had previously ordered inclusion of these patents since 2003.
The expanded gazette improves transparency and legal certainty for pharmaceutical stakeholders, though the listing itself does not confer additional legal rights on the patents.
The Mexican Institute of Industrial Property (search) (IMPI (search)) has made a landmark change to its pharmaceutical patent linkage system by including second-use patents in its October 30, 2025 Linkage Gazette for the first time in over two decades. This development represents a significant shift in Mexico's approach to pharmaceutical patent transparency and regulatory oversight.
Historic Policy Reversal on Second-Use Patents
For more than twenty years, IMPI (search) had maintained a restrictive stance against including pharmaceutical patents protecting new therapeutic uses, commonly known as second-use patents, in its official Linkage Gazette. This exclusion persisted despite multiple amparo court rulings ordering their inclusion since the linkage system was established in 2003.
The October 2025 publication breaks this pattern, appearing as an atypical mid-year edition outside IMPI (search)'s traditional February and August publication schedule. According to legal practitioners, this change appears to result from pressure from the United States under the United States-Mexico-Canada Agreement (USMCA) review process.
Many of the newly included patents had previously been relegated to a separate publication known as the "Gazette of Rejected Patents," formally titled "In-force patents that do not comply with Article 162 LFPPI," which identified patents excluded from the linkage system.
Enhanced Transparency and Legal Certainty
From a practical standpoint, this development improves transparency and legal certainty for all stakeholders seeking to understand the patent landscape of pharmaceutical products in regulatory processes in Mexico. While the Gazette itself does not confer additional legal rights on the patents it lists, its expanded scope provides clearer guidance for pharmaceutical companies navigating Mexico's regulatory environment.
The inclusion of second-use patents may signal a shift in IMPI (search)'s approach to patent listings, potentially setting a precedent for future editions and indicating a more flexible and adaptive practice in managing pharmaceutical patent information.
Simultaneous Format Changes Create New Challenges
Alongside this positive development, IMPI (search) introduced a substantial modification to the Gazette's format in its August 20, 2025 edition. The organization no longer reproduces the most "relevant claims" of patents but instead provides links that redirect to the Letters Patent documents.
This format change presents new challenges for the linkage system, as access to information becomes more complex for all parties involved, including the Federal Commission for the Protection against Sanitary Risks (search), IMPI (search), and users. Reviewers must now analyze all granted claims rather than focusing on previously highlighted relevant claims, making the process more time-consuming and complex.
The Federal Law for the Protection of Industrial Property requires IMPI (search) to publish the Gazette at least twice yearly, including all patents applicable to allopathic medicines (search), along with patent terms and International Nonproprietary Names (INN). However, the law remains silent regarding the publication of specific or relevant claims.
Implications for Pharmaceutical Industry
Legal experts suggest that avoiding publication of the most relevant claims may provoke criticism due to the lack of specific information, as not all patent claims should be reviewed during the linkage process. The modification means that when requesting patent inclusion in the Linkage Gazette, whether before IMPI (search) for active ingredient and pharmaceutical composition patents or through Constitutional Action for non-listed patents, the most relevant claims should be specifically mentioned.
This latest publication reflects an evolution of Mexico's linkage system, demonstrating that IMPI (search) can respond to both domestic and international regulatory and commercial requirements. The changes suggest a more adaptive approach to pharmaceutical patent management, balancing transparency requirements with practical implementation challenges.