A regulatory change that modernizes the filing of inventions
Effective October 1, 2025, the European Patent Office (EPO) will allow color and grayscale figures to be included in electronic patent applications. This regulatory change represents a significant step forward in the digitization of patent procedures, facilitating a more accurate and visually clear representation of inventions.
Until now, the regulations required that all figures be submitted in black and white, even in cases where color was essential to illustrate technical aspects. Under the new measure, combinations of color, grayscale, and black-and-white figures will also be accepted, providing applicants with greater flexibility.
Why is this change significant?
Drawings are an essential element in the description and understanding of an invention, especially in those fields of technology where visual representation—and, more specifically, thecolor component—is crucial to understanding the proposed technical solution.
This change thus provides greaterflexibility for applicants who, until now, could only file patents with black-and-white drawings. However, this new option comes with certain limitations and recommendations that should be taken into account.
What about international applications (PCT)?
It is important to note that this new optiondoes not apply to international applicationsfiled under the Patent Cooperation Treaty (PCT). Although it is possible to include color or grayscale figures in a PCT application, these will be converted to black and white upon international publication, in accordance with the provisions of the PCT system.
However, when an international application is filed electronically, the International Bureau retains the original version in color or grayscale. This version will be available to both the public and national or regional offices through thePATENTSCOPE platform, and the cover page of the publication will indicate whether this version is accessible.
ForEuro-PCT applicationsthat enter the European phase on or after October 1, 2025, the examination of the application will be based on color or grayscale drawings, provided that they are available in PATENTSCOPE and that the international publication expressly states this.
Technical and Legal Recommendations for Applicants and Professionals
This regulatory change introduces new considerations that applicants and industry professionals must take into account.Patent agents must be thoroughly familiar with the technical details of submitting color or grayscale figures, especially when these figures are submitted in the electronic formats required by the EPO.
The technical quality of the figures will also be another determining factor, since an incorrect or inadequate presentation can affect both the technical understanding of the invention and its legal protection.
In addition, it is recommendednot to refer in the text(description, claims, or abstract) to specific color characteristics of the figures, such as “yellow” or “cream.” This is because color specifications cannot always be identified objectively and unambiguously, which could lead to legal ambiguities.
Modified figures and omitted elements: What are the limits?
The option to file color drawings also applies toelectronic amendmentsmade on or after October 1, 2025. However, these must comply with the conditions set forth in Article 123(2) of the European Patent Convention (EPC) regarding added matter.
Figures that have been modified in response to an objection may contain color or grayscale content only to the same extent as the original figures submitted.
Similarly, in the case of omitted elements or corrected figures, applicants must ensure that these correspond exactly to the content and format of the figures in the priority application. If the original figures were submitted in black and white, any corrected or omitted figures must adhere to that format.
What implications will this have for the validation of European patents in Spain?
Once the European Patent Office has granted and published a European patent containing drawings in color or grayscale, the Spanish Patent and Trademark Office will require the applicant seekingvalidation of that European patent in Spain to ensure that the Spanish translation includes the drawings in color or grayscale.
The EPO’s decision to allow color and grayscale figures in electronic applications marks a milestone in the evolution of the European patent system. This measure not only improves the quality of technical disclosure but also poses new challenges for applicants and industry professionals, who will need to adapt their filing strategies and ensure compliance with the applicable technical and legal requirements.
At Elzaburu, we have a team specializing in European patents that can help you prepare your application in accordance with the EPO's new requirements.
Ruth Sánchez, Partner in the Patent Practice at Elzaburu and European Patent Attorney.