Fachmann prüft Farbzeichnungen für europäisches Patent, Fokus auf Innovationen und Rechtssicherheit. — Image created with AI

General 12. March 2026 · 4 min read

Admissibility and practice of color drawings in the European patent system from 2026 onwards

From October 1, 2025, and with the 2026 Examination Guidelines, color and grayscale drawings will no longer be the exception in the European patent system, but rather a regular part of official practice. From 2026 onwards, this will result in a number of new pitfalls—and opportunities—for application strategy, priority, and disclosure.

Legal basis and temporal scope of application

The basis for this is the President’s decision and the EPO notice on color drawings (OJ EPO 2025, A49 and A57).
From October 1, 2025, all EP applications filed electronically may contain color or grayscale drawings; end-to-end processing will take place without conversion to black and white, including publication and the patent certificate.
The 2026 guidelines systematically integrate color drawings into Part A (filing/formal examination) and Part A-IX (drawings), including rules on filing conditions, sheet arrangement, execution standards, and replacement drawings.

Formal requirements for color drawings

Drawings may be in color or grayscale, but must be “sufficiently contrasted” and remain clearly recognizable at 300 dpi; this is checked as a formal requirement (Rule 57 EPC).
Lines, hatching, and areas must continue to be uniform, permanent, and well defined; the requirements for sheet format, margins, reference signs, and legibility from A-IX remain unchanged and now explicitly apply to color drawings as well.
Mixed sets (partly black and white, partly in color) are permissible as long as all sheets meet the same formal criteria.

Submission, exchange, and replacement of drawings

Color or grayscale drawings are only accepted if they are submitted via the EPO’s electronic filing tools; paper documents remain effectively limited to black and white.
Detailed requirements for corrections or replacement drawings under Rule 58 EPC are set out in A‑IX 10.1: replacement sheets must be of the same type (color/grayscale/black and white) and format as the drawings originally filed.
Subsequently published replacements with different coloring may be considered an inadmissible addition of information; the guidelines emphasize that the color reproduction must not convey any new technical information.

Priority, disclosure, and Euro-PCT

When missing drawings are submitted subsequently under Rule 56 EPC, they must correspond “exactly to the content and format” of the priority documents; if the priority drawings were black and white, the subsequently submitted EP drawings must also be black and white.
Color drawings can only support the priority effect to the extent that the corresponding color disclosure was already present in the priority application; Articles 87/88 EPC apply “including” color and grayscale content.
For Euro-PCT applications filed on or after October 1, 2025, the EPO will only process color drawings if certain technical and procedural conditions are met; otherwise, black-and-white reproductions will continue to be used, with corresponding examination under Art. 123(2) EPC for subsequent color submissions.

Practical implications and best practices from 2026

The EPO communication expressly advises against defining color-specific features in the description, claims, or abstract (“red,” “yellow,” etc.), as color nuances are not always objectively reproducible and justiciable.
For divisional applications with color drawings, compliance with Art. 76 (1) EPC must be “carefully checked” to ensure that the coloring does not go beyond the disclosure of the parent application.
Out of caution for disclosure and priority issues, many practitioners continue to recommend primarily black-and-white drawings despite the new freedom—at least as long as important target countries outside the EPC do not yet accept color as equivalent.

Note and practical example

Anyone wishing to use color drawings in the European patent system from 2026 onwards should proceed strategically: priority applications, EP submissions, and any PCT continuations must be consistent in terms of coloration, and the description should not define technical features solely by means of color specifications. A practical example is chemical or medical technology illustrations, where color coding (e.g., different types of tissue or fluids) improves readability without the color itself being used as a feature justifying the claim.