4.2.8Drawings 

4.2.030The requirements governing the representation of your invention in the drawings are set out in Article 1 of the EPO President's decision dated 25 November 2022 on the presentation of application and other documents. Reference signs not mentioned in the description and claims must not be used in the drawings, and vice versa. The same features, when denoted by reference signs, must be denoted by the same signs throughout the application. 

4.2.031Drawings must not contain text matter except, when absolutely indispensable, keywords such as "water", "steam", "open", "closed", "section on AB" and, on electric circuits and block schematics or flow sheet diagrams, short catchwords indispensable for understanding. Any such keywords must be placed in such a way that they can be replaced by their translations without interfering with any lines of the drawings. 

4.2.032Flow sheets and diagrams are considered to be drawings. 

4.2.033Good-quality drawings are very important for the correct disclosure of the invention. If the drawings are unreadable, e.g. completely black, you may not be allowed to file better-quality drawings at a later stage, disclosing more details than those originally filed. 

Although the EPC has no express provisions for photographs, they are nevertheless allowed. Colour photographs are scanned and made available in the electronic file in black and white.