On March 18, 2026, the Executive Branch of the Republic of Argentina repealed the so‑called Pharmaceutical Guidelines, which had entered into force in 2012 and significantly restricted access to patent protection by automatically categorizing a wide range of subject matter as non‑patentable, including, among others, crystalline forms, enantiomers, selection inventions, formulations, salts and esters, and Markush‑type claims. 

As a result of this rescission, new patent applications as well as those currently pending are now subject to a broader standard of patentability, granting the National Institute of Industrial Property (INPI) a substantially more technical and independent role in the examination and prosecution of pharmaceutical and biotechnological inventions in Argentina. 

Until now, the Pharmaceutical Guidelines imposed strict restrictions on inventions in the pharmaceutical field, establishing significant limitations for complying with various patentability requirements. Specifically, they included the following patentability restrictions: 

• Solid forms (polymorphs, pseudopolymorphs, crystalline forms, hydrates and solvates): were not considered patentable because they correspond to the simple identification of physical forms of matter that do not depend on human intervention. 

• Enantiomers: were considered inherently lacking novelty if prior art disclosed the racemic mixture, even if the specific enantiomer was not explicitly disclosed. 

• Salts, esters, and derivatives: were considered lacking novelty, as they were deemed equivalent to the base compound existing in the prior art. 

• Markush formulae: These were considered to lack clarity and descriptive support, as they required that all covered alternatives were perfectly disclosed and their scope be restricted to what could be reproduced from the examples and for which evidence was provided that it solved the technical problem, which in practice meant that they had to be restricted to the exemplified compounds. 

• Selection inventions: these were deemed to lack novelty, as it was considered that the previous disclosure included each and every one of the covered alternatives, even though explicit disclosure of all of them was not provided. 

• Formulations and compositions: these were considered inherently obvious, as their preparation and obtaining any potential advantages was considered routine work. 

Pursuant to this regulatory change, these restrictions are removed, and INPI will modify its practices to align them with the criteria applied by the world’s leading patent offices. However, INPI has not issued new guidelines to replace the recently repealed ones, so the specific application of these new practices will be analyzed on a case-by-case basis. 

While there is no clarity regarding the specific criteria that will be applied in the examination of patent applications in the chemical and pharmaceutical field, the practice followed by the INPI before 2012 – prior to the issuance of the Pharmaceutical Guidelines – may constitute a precedent to guide the new examinations.  

In this sense, the guidelines applied prior to the Pharmaceutical Guidelines did not impose any strict restrictions on the types of inventions listed above. In fact, these earlier guidelines recognized that compositions could be patented if they had a special and unexpected effect. Similarly, they indicated that selection inventions could be patented when they demonstrated a superior and unexpected effect compared to general disclosure. Thus, the practice prior to the Pharmaceutical Guidelines showed a clear alignment with the patentability examination criteria used by most patent offices, allowing, among others, the granting of patents related to pharmaceutical compositions, crystalline forms, or selection inventions. 

Therefore, and despite the fact that there are no specific guidelines for the chemical and pharmaceutical sector, it is expected that from now on INPI will take less restrictive positions and be more focused on compliance with the requirements of novelty, inventive step and industrial application, returning to the approach it applied before the issuance of the Pharmaceutical Guidelines and aligning itself with international practices. 

Transitional arrangements for products available in the market 

The new regulatory framework also establishes a transitional regime, providing special protection for pharmaceutical products that are currently on the Argentinean market. Consequently, patent applications granted from this date onward that cover components or pharmaceutical products already being commercialized in Argentine territory will not confer upon their patent holders the right to prevent the continued commercialization thereof, nor to claim damages or compensation. 

The repeal of the Pharmaceutical Guidelines in force since 2012 represents a turning point in Argentina’s patentability policy, aligning the system with broader international standards. Nevertheless, it will be essential to closely monitor the practical application of these new criteria by the INPI, as well as the evolution of administrative and judicial case law in this area.