The change applies to all electronic filings of European patent applications via the EPO (Online Filing 2.0, ePCT, the EPO Contingency Upload Service and MyEPO), including divisional applications. Although colour drawings are not permissible in PCT applications, colour/greyscale drawings may be available online for a PCT application and noted in the application itself (see below).

The EPO states that this change is based on user demand, the ability to deal with such applications in view of end-to-end electronic processing and publication, and aligns more broadly with general digitalisation goals.

European patent applications

Colour and/or greyscale drawings can be included in European patent applications and divisional applications. However, for divisional applications, the drawings will be examined for compliance with Article 76(1) EPC to ensure that subject matter does not extend beyond that found in the parent application.

Similarly, if there are missing parts or corrections to drawings under Rules 56(3) or 56a(4) EPC, the drawings should correspond directly to those of the priority application. Accordingly, the applicant is limited to the drawings filed in the priority application.

PCT applications for which the EPO is receiving office

Colour drawings do not currently fulfil formality requirements for PCT applications, although this is currently in discussion as outlined in PCT/WG/17/12.

Nevertheless, the EPO as receiving office will accept colour drawings. These will be converted to black and white by the International Bureau, but the colour drawings will remain available to the public and national offices on PATENTSCOPE and will be noted on the front of the application.

This becomes relevant to PCT applications entering the European regional phase.

For Euro-PCT applications entering the European phase from 01 October 2025, the EPO will process colour drawings that are both: 1) available on PATENTSCOPE; and 2) mentioned on the front page of the application. If either criterion is not fulfilled, the drawings will be processed in black and white.

For Euro-PCT applications entering the European phase before 01 October 2025, the possibility of amendment is mentioned in the Official Journal (EPO OJ 2025, A57, point 11), noting that such drawings will be assessed for compliance with Article 123(2) EPC.

Translated applications

For European applications originally submitted in a non-EPO language and then translated (Article 14(2) and Rule 6(1) EPC), the drawings must correspond to those of the original application.

For Euro-PCT applications that require translation (Article 153(4) and Rule 159(1)(a) EPC), as with other Euro-PCT applications, if colour drawings are available on PATENTSCOPE and noted in the application, these will be processed.

Priority

Later applications claiming the priority of an earlier application can, within the bounds of Articles 87 and 88 EPC, utilise colour drawings where the priority application includes colour drawings.

Changes to the implementing regulations

Decision of the President of the EPO dated 07 July 2025 under Rule 49(2) EPC provides:

“(2) Drawings shall be executed as follows:

(a) Drawings shall be executed without colourings in durable, black, sufficiently dense and dark, uniformly thick and well-defined lines and strokes. When filed by means of electronic communication, drawings may also be executed in colour or in greyscale, in durable, uniformly thick and well-defined lines, strokes or areas. They must also be sufficiently rich in contrast and suitable to be clearly displayed at a resolution of 300 dpi.” (Emphasis added)).

The meaning of “sufficiently rich in contrast and suitable to be clearly displayed” is open to interpretation, but the acceptance of colour and/or greyscale drawings clearly offers the opportunity to convey more detailed technical information.

Other jurisdictions

Colour drawings are not widely accepted in other jurisdictions. In the IP5, only Korea generally accepts colour drawings. The USA and China only accept colour drawings if necessary for explaining the technical content of an application. Japan accepts only black and white or greyscale.

Closer to home, the UKIPO only accepts black and white drawings, although photographs which inherently include greyscale are also allowable.

Risks and best practice

Although there are likely to be some practice points to iron out, the change to accept colour and/or greyscale drawings appears to be a step forward. That said, the biggest risk to applicants submitting colour drawings is loss of information if the drawings need to be converted to black and white. For cautious applicants, particularly where the application is to be submitted in jurisdictions that do not allow colour, best practice may be to continue to prepare and submit black and white drawings. For other applicants, particularly where the application is to be submitted in jurisdictions generally allowing colour or allowing colour where justified, best practice may be to submit drawings in colour, with the potential fallback of readability if converted to greyscale.