Introduction
The European Patent Office (EPO) has released previews of the updated Guidelines for Examination, which will officially come into force on 1 April 2025. From that date, the EPO will provide three distinct sets of guidelines. The Guidelines for Examination in the European Patent Office ("EPC Guidelines") and the Guidelines for Search and Examination at the European Patent Office as PCT Authority ("PCT-EPO Guidelines") outline procedures for European and international patent applications under the European Patent Convention (EPC) and the Patent Cooperation Treaty (PCT). Additionally, the Unitary Patent Guidelines ("UP Guidelines") detail the processes for obtaining, maintaining, and managing Unitary Patents based on the EPC.
This article focuses solely on the key modifications to the Guidelines for Examination. While numerous minor adjustments have been made, the discussion below highlights only the most significant changes.
Updates on Communication with the EPO in the 2025 Guidelines
A portion of the modifications in the 2025 EPO Guidelines concerns communication with the EPO, particularly the introduction of MyEPO Portfolio and the discontinuation of fax-based communication.
Language of Proceedings for Euro-PCT Applications
The updated section E-IX 2.1.4, which replaces the previous E-IX 2.1.3, clarifies the rules governing the language of proceedings for Euro-PCT applications. When an international patent application is published under Article 21 PCT in one of the official EPO languages, that language automatically becomes the language of proceedings. However, if the publication occurs in a different language, the applicant must submit a translation into an official EPO language, which then determines the language of the proceedings. Once set, the language of proceedings cannot be changed.
The revision also specifies the consequences of submitting amendments or translations in an EPO language that is not the official language of the proceedings. As previously established by the Enlarged Board of Appeal in G 04/08, such submissions are considered "not duly filed" and cannot serve as a basis for processing the Euro-PCT application. The EPO will notify the applicant accordingly.
Although using the incorrect EPO language does not result in a loss of rights, it may lead to unnecessary costs associated with translations, rewriting amendments in the correct language, and, in cases where submissions occur near deadlines, incurring additional fees for further processing under Article 121 EPC. This issue is particularly relevant when a case is transferred to a new applicant or a new European patent attorney at short notice, where miscommunication regarding the language of proceedings may lead to unintended errors.
Correction of Errors in Filed Documents
The revised section H-VI 2.2 presents a more structured overview of the conditions under which corrections to filed documents may be made under Rule 139 EPC. As outlined by the Enlarged Board of Appeal in G 1/12, a valid correction must introduce what was originally intended at the time of filing. Additionally, if the correction is not immediately apparent, the applicant bears a heavy burden of proof to justify the requested amendment.
The error in question may involve an incorrect statement or an omission, but the correction must be requested without undue delay. It is important to note that Rule 139 EPC does not allow applicants to make corrections based on a change of mind at a later stage; instead, the correction must reflect the actual intent at the time of filing. Given the stringent requirements, it is advisable to act swiftly once an error is detected. In practice, initiating internal steps to correct mistakes on the same day they are identified helps prevent objections based on undue delay.
Both amendments regarding language of proceedings and document corrections serve to clarify legal positions and provide clearer procedural instructions. They emphasize practical approaches to ensure applicants comply with the established rules while minimizing unnecessary procedural disputes.
Clarifications regarding AI and Machine Learning
The revised Part G-II 3.31 provides a more refined definition of artificial intelligence and machine learning. One change is the removal of explicit references to the purpose of computational models and algorithms, which previously included classification, clustering, regression, and dimensionality reduction. Instead, the guidelines now focus solely on listing representative examples of AI-related algorithms, such as artificial neural networks, genetic algorithms, support vector machines, k-means, kernel regression, and discriminant analysis.
Another update explicitly recognizes that while computational models and algorithms are inherently mathematical and abstract, this does not automatically render them non-patentable. The burden of demonstrating technical character and inventiveness lies with the applicant. To clarify this, the updated guidelines align AI-related inventions with other computer-implemented inventions (CIIs). If a claim related to artificial intelligence or machine learning is directed to a method that involves the use of technical means, such as a computer, or to a device, its subject matter is considered to have technical character as a whole and is therefore not excluded from patentability under Article 52(2) or (3) EPC. In such cases, computational models and algorithms contribute to the technical character of the invention if they help solve a technical problem. This can be demonstrated by their application in a specific technological field or their adaptation to a particular technical implementation.
These changes do not introduce new legal principles but instead reflect the current approach of EPO examiners when assessing AI-based inventions. As AI-related patent applications increase, it is essential for applicants to emphasize the technical contribution of their inventions.
A practical strategy when drafting AI patent applications is to describe how the AI model interacts with other software components or technical systems. One effective way to achieve this is to frame the AI system as a control mechanism rather than simply a classification tool. For instance, rather than describing a neural network as performing classification, applicants should consider explaining how the neural network generates control data to regulate a technical process, machine, or software component. This approach strengthens the argument that the invention has a clear technical purpose.
Conclusion
The 2025 revisions to the EPO Guidelines for Examination introduce refinements in procedural and substantive matters, with particular emphasis on communication methods, procedural language requirements, error correction, and the treatment of AI-related inventions.
For applicants seeking to patent AI inventions, ensuring that claims emphasize a specific technical purpose remains key. Furthermore, framing AI within a broader technical system or control framework rather than as an abstract computational model improves the likelihood of success. With the growing importance of AI in various industries, understanding these modifications will be essential for patent practitioners and inventors navigating the European patent system. Even though these changes come into effect on 1 April 2025, they merely confirm the existing examination practice rather than introducing fundamental changes, ensuring consistency in how AI inventions are assessed.
Talk to us and contact us for further information at:
Phone: +49 (0)611 / 341568-0
Fax: +49 (0)611 / 341568-11
E-mail: Send email to us
PGP-Key
Author: Dr. Brian George Heil and Dr. Julius S. Cohen