Double patenting objections

On 5 November 2020 the Federal Law of Protection for Industrial Property came into force and introduced provisions explicitly concerning double patenting for the first time in Mexico.

Double patenting objections

Issuing double patenting objections is a common practice for the Mexican Institute of Industrial Property (IMPI) when examiners consider that the invention to be protected in a divisional application is already covered or protected by the parent case. However, this kind of objection is commonly based on Articles 43 and 44 of the Industrial Property Law, which still governs the patent system in Mexico for applications filed prior to 5 November 2020 and contains no explicit provision prohibiting double patenting in Mexico.

Article 43 of the Industrial Property Law indicates that a patent application must reference a single invention or a group of inventions linked by a single inventive step. Article 44 indicates that, if a patent application does not meet the provisions of Article 43, the IMPI will request the applicant to divide the application. However, both articles are silent in relation to double patenting objections and filing voluntary divisional applications.

Since double patenting objections are issued based on Articles 43 and 44, the criterion for the IMPI to raise this kind of objection is that:

  • the matter of the voluntary filed divisional application cannot be granted since the IMPI did not request the applicant to divide the parent case; and
  • the applicant should have no interest in pursuing the same subject matter already granted in the parent case.

This criterion contravenes both the IMPI's practice for decades of receiving voluntary divisional applications and also what is established in Article 4-G of the Paris Convention for the Protection of Industrial Property, which allows applicants on their own initiative to divide a patent application.

The Federal Law of Protection for Industrial Property (FLPIP) addresses the Industrial Property Law's silence on double patenting by introducing an article which explicitly establishes that no patent – divisional or not – will be granted for a matter that is already protected by another patent or where the essential technical features are a non-substantial variation of the matter covered by the same, even when the applicant is the holder of the first right (ie the parent case (Article 101 of the FLPIP)). Further, the new FLPIP considers the provisions of the Paris Convention, as Article 101 of the FLPIP indicates that the applicant may voluntarily divide an initial application that is still pending, keeping the filing date of the divisional application as the same date as the parent case and, where appropriate, the date of the priority claimed as long as the divisional application complies with Article 100 of the same FLPIP.

Considering the content of Articles 100 and 101 of the FLPIP, it seems that double patenting objections will be issued for patent applications that according to the examiners' criteria pursue the same or substantially the same technical features than those granted in the parent case.

In this regard, although Article 100 indicates that no patent will be granted for a divisional application of which the essential technical features are a non-substantial variation of the matter covered by the parent application, the FLPIP does not indicate how it will be determined whether the features of a divisional application correspond to a substantial variation from those in the parent case.

However, this issue might be defined in the Regulation for the FLPIP, which is pending issuance. Otherwise, the new criteria on whether a difference in a patent claim relates to another is non-substantial will have to be established on a case-by-case basis in the patents' prosecution history. It could be several months or maybe years until the first applications filed after 5 November 2020 reach substantive examination.

For further information on this topic please contact Edwing Sandoval at Becerril, Coca & Becerril SC by telephone (+52 55 5263 8730) or email ([email protected]). The Becerril, Coca & Becerril website can be accessed at