Divisional applications are excellent for protecting additional embodiments of an invention. In many technology fields, and especially in the pharmaceutical industry, divisionals are a frequently used tool to create robust protection for a certain patent portfolio. Of course, Mexico is not an exception and for many years patent owners have filed many divisional applications either voluntarily or as a result of a lack of unity objection. This scenario has changed as a result of our new law that entered into force on November 5, 2020, which contains several limitations for filing divisional applications. Moreover, in the last few months, several erroneous interpretations from the Mexican Patent Office (IMPI) have further complicated the current scenario for filing divisionals in Mexico.

Divisionals before November 5, 2020

Before the Federal Law for the Protection of Industrial Property (FLPIP) entered into force on November 5, 2020, the applicable law was the former Intellectual Property Law (IPL) which had been in force since 1991. This previous law only specifically contemplated the scenario of filing a divisional application as a result of a lack of unity objection but, in practice, examiners also accepted voluntary divisionals as long as they were filed at any time during the prosecution of the parent case and before the payment of the grant fees. There was no limit to the number of voluntary divisionals that could be filed and no limitation for filing cascade divisional applications, it was frequent to see fourth and even sometimes fifth generation divisionals.

IMPI's practice for voluntary divisional applications was supported in Article 4G(2) of the Paris Convention which says that:

"Voluntary divisionals deriving from divisionals will no longer be allowed. "

"The applicant may also, on his own initiative, divide a patent application and preserve as the date of each divisional application the date of the initial application and the benefit of the right of priority, if any. Each country of the Union shall have the right to determine the conditions under which such division shall be authorized"

This practice went on for over three decades and was seen as positive by most patent owners.

Divisionals from November 5, 2020, and onwards

As previously mentioned, on November 5, 2020, our Federal Law for the Protection of Industrial Property (FLPIP) entered into force and this new law specifically contemplated the possibility of filing voluntary divisional applications. However, this new law also contemplated several limitations for filing divisionals which were absent in the former law which are mentioned below.

a) Cascade divisionals

As mentioned in Article 100 of our new IP Law, a voluntary divisional application will only be possible if it derives from its parent case. In other words, voluntary divisionals deriving from divisionals will no longer be allowed. The only possible scenario for filing cascade divisionals is if the Mexican PTO requests further division through a lack of unity objection.

It is also possible to file multiple divisional applications all deriving from the same parent case.

A possible solution to this new situation is to file in the first divisional a set of claims that do not comply with unity of invention in order to ensure that the examiner issues a lack of unity objection, thus allowing the applicant to file further divisional applications in the future.

b) Limitations on claimed subject matter in divisionals

One major change in divisional practice is that now, when unity of invention is objected to, any invention or group of inventions that are not included in the initial application, or in the application that originated, the division cannot be included again in any of said applications. Therefore, when receiving a unity objection, the applicant needs to consider this when deciding the scope of protection that is of commercial interest to them. If this is not yet clear, it is important to not let go of any matter when dividing the application.

c) Double patenting

Double patenting has long been an issue in Mexico and, in practice, examiners tended to raise double patenting objections when there is scope overlap between the claims of a divisional and that of its parent case. However, double patenting was not defined in our previous law, so it was feasible to argue that the only scenario in which double patenting existed was if the scope of the claims of the divisional was identical to the scope of the claims of the parent case.

Article 101 of our new law mentions that a patent will not be granted to a matter that is already protected in another patent or if the essential technical characteristics sought to be protected are a non-substantial variation of the matter protected in said other patent. This definitely poses a grey area on how double patenting will be assessed by the examiners and how they will interpret a "non-substantial variation". The assessment of the examiners will depend on the pertinent case law that will develop once these cases reach the Mexican courts.

"MPI started denying all voluntary cascade divisional applications regardless of whether the parent case was filed before or after November 5, 2020. "

The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.