The payment of maintenance fees in Mexico for patents, Design Registrations, Certificates of invention and Utility Models, changed as of 1995, in view of the fact that up to August 31, 1995, these payments had to be done every year in the month of January.
Now, as of September 1st, 1995, the payment of the annuities must be done every five years, that is, in a quinquennial manner. Taking this into account, the annuity payments in Mexico must be effected this year (2000), for those cases which were granted between September 1st and December 31, 1995.
Such payments could have been done in January and if not, they can still be done on the Anniversary month of the Legal Date, having six months of grace term counted as of this Anniversary date, for effecting belated payment.
It is to be noted that for PCT National phase patents, the legal date corresponds to the filing date of the PCT application.
For divisional patents, the date to be considered as the legal date is the one corresponding to the first application from which the divisional patent derived.
There is another type of matters called PIPELINE patents, which must be very well identified because although the legal date is the one of filing in Mexico, the lifeterm for which they were granted corresponds to that of the first application filed in a PCT country. Therefore, in these cases, we may run the risk of paying more annuities than the necessary ones, if the lifeterm granted by the Mexican Patent Office in this kind of patents is not very well identified.
The content of this article is intended only to provide general guidelines related to this particular matter. For your specific circumstances, full specialist advice is recommended.