The Mexican law now requires a Declaration of Actual and Effective Use (similar to the USA, the Philippines and Mozambique) to be filed three years after registration and at the renewal date of an IR mark. No samples or other pieces of use evidence are required. However, an official fee has to be paid, and the declaration must be filed by local counsel (further information available under https://www.wipo.int/edocs/madrdocs/en/2018/madrid_2018_13.docx.).
Notably, the three-year period is not calculated from the date of the granting notification WIPO sends to the international trademark holders, but from the national Mexican registration date available only in the database of the Mexican Patent and Trademark Office.
As far as IR marks designating Mexico are concerned, this new formal obligation applies to all trademarks having a renewal date or a registration date after August 10, 2018 in Mexico. Consequently, no steps have to be taken before August 10, 2021.
For all IR marks covering Mexico, the actual granting date has to be checked through a local Mexican counsel in order to calculate the three-year period. The WIPO notification date is only a rough indication. The new use declaration requirement creates new burden for IR owner and thus makes Mexico less attractive for IR coverage.