A proper representation of an invention is key to its protection. That is why the new regulation allowing the use of colour drawings for European patents represents a fundamental change for inventors and companies. Starting from the upcoming October 1, 2025, the European Patent Office (EPO) will officially accept colour and greyscale drawings in electronically filed applications.
This is a long-awaited change for the innovation community and marks a step towards the modernisation of intellectual property in Europe.
Why are colour drawings important for European patents?
Until now, although colour drawings could be submitted, they were converted to black and white at the time of publication. This conversion, in many cases, meant a critical loss of information for the description of the invention.
Imagine a biotechnological invention with a graph where different colours represent different protein sequences, or a user interface design where colour is key to functionality. When converted to black and white, the clarity of the invention could be lost.
This new regulation for filing patent drawings opens the door to a much more faithful representation in fields such as:
- Biotechnology and chemistry
- Medical devices and health technology
- Software and graphical interfaces
- Engineering and industrial design
This update responds to a long-standing demand, as the use of colour drawings for European patents is an essential tool for describing complex creations with greater precision.
Technical Requirements of the EPO for the New Drawings
The EPO has established clear technical requirements to ensure the quality of the images. Colour drawings for patents must have well-defined lines, high contrast, and be perfectly visible at a 300 dpi resolution. In essence, the EPO aims to ensure that what is seen is exactly what is intended to be protected, without ambiguities in the patent application.
What about International (Euro-PCT) Applications?
This is where we must pay close attention if your patent protection strategy is international via the Patent Cooperation Treaty (PCT).
Currently, the publication of a PCT application remains in black and white. Therefore, for the EPO to accept colour drawings in the European phase of a Euro-PCT application, it is essential that said drawings are available in colour on the PATENTSCOPE database and that the international publication mentions this.
This is a crucial technical detail that can affect the validity of the application as filed. Improper handling of this aspect could have consequences on the scope of patent protection in Europe.
Colour Drawings: How Do Other Patent Offices Handle Them?
With this measure, the EPO joins offices like South Korea’s (KIPO), which already accepted colour, or those of the United States (USPTO) and China (CNIPA), which accept it when necessary. However, other major offices such as Japan’s (JPO) or the United Kingdom’s (UKIPO) still require, for the time being, the black and white format for patent submissions.
Our Recommendations
This regulatory change by the European Patent Office is excellent news, providing both flexibility and precision.
- For direct European patent applications, we recommend leveraging the advantages of colour whenever it adds descriptive value.
- For protection strategies via the PCT, we advise caution. The safest option remains to prepare high-quality black and white drawings that meet the requirements of all offices. If colour is indispensable, it is crucial to plan the strategy with a patent attorney to ensure the conditions for the European phase are met.
In summary, the arrival of colour drawings for European patents is excellent news, but its application requires a well-defined strategy to maximise its benefits and avoid risks.
At ISERN Patentes y Marcas, we understand the impact of this regulation and are ready to guide our clients. If you are seeking advice on patents and trademarks or have questions about how this change affects your portfolio, we are at your disposal.
Frequently Asked Questions (FAQ) about the new EPO regulation
The new regulation comes into force on October 1, 2025. All European patent applications filed electronically on or after that date may include colour or greyscale drawings.
No, the European Patent Office has not announced any additional official fees for filing colour drawings. The costs associated with the application will remain the same.
Yes, that is a possibility. From October 1, 2025, amendments including colour drawings may be filed for existing applications. However, it is crucial that these new drawings do not add subject-matter that extends beyond the original disclosure, so as not to affect the patent’s validity.
Not necessarily. Our recommendation is to use colour only when it provides real, clarifying value for describing the invention. If black and white is sufficient for a complete understanding, it remains the safest and most universal option, especially if you plan to protect your patent in countries that do not yet accept colour (such as Japan or the United Kingdom).
The main risk is procedural. The international publication of a PCT application remains in black and white. For the EPO to accept the colour version in the European phase, it must be available and correctly referenced in the international databases. An error in this step could lead the EPO to consider that the colour version is not part of the original application, which would affect the scope of your protection. It is a step that requires expert handling.