Navigating Divisionals in Mexico: From Pre-2020 Practice to the Modern FLPIP Regime

This post forms part of our comprehensive 18-part series on divisional patent applications around the globe. Each installment explores unique local requirements, practical pitfalls, and strategic insights from leading jurisdictional experts. Whether you're a seasoned patent professional or new to international filing, this series demystifies divisionals, helping you maximize the value and life of your patent portfolios.

Introduction to Divisionals in Mexico

In the complex terrain of Mexican patent law, divisional applications have held a particularly dynamic role. Mexico’s shift from the former Intellectual Property Law (IPL) to the Federal Law for the Protection of Industrial Property (FLPIP) on November 5, 2020, significantly changed the landscape for both voluntary and examiner-driven divisionals. Before 2020, practitioners enjoyed broad flexibility, often filing multiple generations of voluntary divisionals at virtually any point during prosecution as long as there was one divisional in the family pending. The new regime, however, brought structured limitations and narrower pathways, particularly restricting cascade divisionals unless a lack of unity objection is in play. This regulatory evolution—still clouded by unsettled secondary regulations—presents both challenges and opportunities for applicants seeking optimal patent protection in Mexico.

Divisionals prior to November 5, 2020

A new intellectual property (IP) law became effective in Mexico on November 5, 2020. Before the current Federal Law for the Protection of Industrial Property (FLPIP) became effective, the applicable law was the former Intellectual Property Law (IPL). The IPL specifically allowed for the filing of a divisional application in response to a lack of unity objection. Still, in practice, Examiners also accepted a voluntary divisional filed at any time during the prosecution of the parent case and before the payment of the grant fees. There was no limit on the number of voluntary divisionals that could be filed, and there was also no limit on filing cascade divisional applications. It was not uncommon to see fourth and even fifth-generation divisionals.

The Mexican Institute of Industrial Property’s (IMPI) practice for voluntary divisional applications was supported in article 4 G (2) of the Paris Convention which states that “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 many years and was seen as positive by most patent owners.

Divisional applications under the current Federal Law for the Protection of Industrial Property

Article 100 of the FLPIP is the main article regulating the filing of divisional applications in Mexico and contemplates the filing divisional applications either voluntarily or through a requirement issued by IMPI, such as a lack of unity objection.  This article also defines the timeframe for filing divisional applications, namely, when responding to the office action that raises a lack of unity objection or voluntarily provided the divisional is filed at any time before the payment of the grant fees. It states that a voluntary divisional application is only possible if it derives from its parent case.  In other words, the filing of voluntary divisionals deriving from divisionals is no longer permitted. The only potential scenario for filing cascade divisionals (e.g., a divisional from a divisional) is if the IMPI requests further division due to a lack of unity objection. Article 100 also states that when a lack of unity of invention is raised, any invention or group of inventions that are not included in the initial application or a divisional application originating from the initial application cannot be included again in any subsequent applications.

Moreover, Article 113 states that when an application lacks unity of invention, the Examiner will consider the invention mentioned first in the claims to be the main invention and will evaluate the compliance of the remaining patentability requirements (e.g., novelty, inventive step, etc.) only for this invention. In this case, IMPI will require the applicant to limit the claims to this main invention, and if the case is, to file the corresponding divisional(s) applications for the other remaining inventions.

Article 113 causes problems in Mexican patent practice because Examiners often raise a series of objections based on this article, which complicates the strategy for filing divisional applications.

There have been cases in which, in a first office action, applicants have received a lack of unity objection. Instead of limiting the claims to the first invention identified by the Examiner, applicants have limited the claims in this parent application to one of the other inventions identified by the Examiner. However, in the second office action, the Examiner responds, stating that according to Article 113 of the FLPIP, the applicant is required to limit the claims of the parent application to the invention mentioned first in the claims and is not permitted to claim any other invention listed in the claims. In some instances, the Examiner has gone as far as requiring the applicant to abandon the parent case and file a divisional application directed to the invention of interest to comply with Article 113.  In our opinion, this interpretation of Article 113 is erroneous and does not benefit applicants. Article 113 only states that when a lack of unity of invention is raised, IMPI will evaluate the invention mentioned first in the set of claims, and the applicant is required to limit the claims of the parent case to those that constitute the “main invention”.  Article 113 does not explicitly state that an applicant is required to limit the scope in a parent case to the invention mentioned first in a set of claims, and that none of the other inventions recited in the claims can be claimed in the parent case. Under this interpretation, IMPI is making an arbitrary decision and forcing applicants to claim in their parent case an invention which may no longer be of commercial interest. 

Another erroneous interpretation we have observed involves the timing for filing divisional applications after an applicant receives a lack of unity objection. We have seen cases where Examiners, based on Article 113, request an applicant to file all the divisional applications of interest when responding to the office action that raised the lack of unity objection. In other words, if in an office action an Examiner raises a lack of unity objection and identifies three inventions, the applicant is required to keep the first invention in the parent case and, when responding to the office action, file a first divisional application directed to the second invention and a second divisional directed to the third invention. This interpretation is completely erroneous as neither Article 100 nor Article 113 contemplates such a requirement.

These erroneous interpretations by Mexican Examiners appear to be the result of a lack of Regulations for the FLPIP.  Even though the FLPIP became effective on November 5, 2020, the Regulations are still in the process of being drafted.  The Regulations currently being applied are those from Mexico’s previous IP law (the IPL), which did not contain any articles regulating the filing of divisional applications. This has created a significant grey area and the issuance of a myriad of different objections due to varying interpretations of the articles relating to divisional applications, such as Article 100 and Article 113.

Double Patenting

Double patenting has long been an issue in Mexico. In practice, before the FLPIP entered into force, Examiners tended to raise double patenting objections when there was an overlap in scope between the claims of a divisional application and those of its parent. However, double patenting was not defined in the IPL. As such, it was possible 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 application from which said divisional derived. This argument was often successful with IMPI.

The FLPIP provides specific provisions regarding double patenting. However, these provisions are vague and leave a considerable grey area for interpretation. Articles 50 and 101 are the articles the refer to double patenting and state: “During substantive examination and in the granting of rights, IMPI shall look out for the public domain and prevent double patenting of the same invention” (Article 50) and “No patent will be granted to matter that is already protected by another patent, or which essential technical characteristics are a non-substantial variation of the matter protected by another patent, even when the applicant is the same in both” (Article 101).

Since the FLPIP does not define what should be considered as a “substantial variation”, Examiners often issue double patenting objections in divisional applications that only have a minor scope overlap with the claims granted in the parent application that originated said divisional and are directed to different subject matter. Thus, there is an urgent need for regulators to define what is considered as a “substantial variation” so that, when Examiners are performing substantive examination they can focus from the beginning on issues relevant to the patentability of the divisional application (e.g., novelty, inventive step, enablement, sufficiency, etc.) instead of spending time and effort searching for any kind of scope overlap with the parent application to justify raising a double patenting objection.

Divisional Filing Requirements

When filing a divisional application, the following documents must be submitted:

1.  A copy of the description and drawings and sequence listing, if applicable;

2.  A set of claims to be pursued; and

3.  If appropriate (e.g., if the Applicant has assigned its rights in the parent application to a third party), an assignment and Power of Attorney.

Documentation relating to the priority claim and translation does not need to be submitted.

The Official Fees for filing a divisional Application are as follows:

1.       Official fees for filing a divisional application, including the examination on the merits of the invention (up to 30 pages) - $352.00 (USD)

2.      Official fees for each additional page (From page 31) - $5.00 USD

3.      Official fees per priority claimed - $83.00 USD

Examination and Publication of Divisional Applications

Like an original (parent) application, a divisional application is examined in chronological order by IMPI and is usually examined by the same Examiner who examined the parent case. Typically, divisionals are examined more quickly than the parent application, and the first office action issues 1 to 2 years earlier than in a parent application. Divisionals are also published in IMPI’s public gazette.

 Conclusion

There have been significant advances in Mexico, such as the new venues for expediting issuance of Mexican applications that have an issued U.S. counterpart through the new Parallel Patent Grant (PPG) and Accelerated Patent Grant (APG) programs, and the existence of patent term adjustment (PTA) due to unreasonable delays directly attributable to IMPI. However, the FLPIP has many grey areas, particularly regarding divisional applications and double patenting. It is of utmost importance that the Regulations for the FLPIP be published as soon as possible to provide a clear path for applicants who seek to protect their inventions in Mexico.

Key Takeaways

• Broader Pre-2020 Flexibility: Before November 5, 2020, voluntary and cascading divisionals were widely accepted, often without substantive restriction on timing or number. The only requirement was that there should be a pending divisional in the patent family.

• Tighter Current Rules: Under FLPIP, voluntary divisionals must directly stem from the parent application, and voluntary cascade divisionals are generally not permitted—except when further divisionals are prompted by unity objections from IMPI.

• Ongoing Regulatory Uncertainty: Absence of finalized FLPIP regulations has resulted in inconsistent examiner practice and less predictable outcomes for applicants.

• Filing and Examination Practice: Divisionals are examined in chronological order (often faster than parents), require specific documentation, and are published in IMPI’s official gazette.

• Strategic Implications: Advanced planning is encouraged; missteps in response to unity objections or misunderstanding examiner discretion can jeopardize future patent protection in this evolving environment.

This post was written by Lisa Mueller and Maurico Samano of Olivares.