Currently the EPO allows drawing to be submitted electronically or on paper but requires the drawings to be rendered in black and white. Where colour drawings have been submitted, currently the EPO converts the drawings to black and white. That conversion may not capture all the detail contained in the submitted drawings, but the applicant bears that risk on account of not having submitted the drawings in black and white. This can be further compounded if the specification, claims or abstract refers to colour specific features of the drawings where those features were not retained in the converted drawings. This can leave the applicant between a rock and a hard place as attempts at amending the drawings so as to recapture all the details in the submitted drawing will risk giving rise to an added matter objection.
Those risks will not be an issue for the following types of electronic applications filed with the EPO from 1st October 2025 that have colour or grey scale drawings:
While PCT international phase applications that are filed with colour or grey scale drawings have those drawings rendered in black and white by the International Bureau (IB), the IB still retains the colour or grey scale drawings so they can be used in national and regional phase for those offices that allow colour or grey scale drawings.
It appears that the EPO will be the first office to allow for the filing of colour drawings as of right. The USPTO only allows for the filing of colour drawings if that is the only practical medium by which to disclose the subject matter in a utility patent application. This requires the additional filing of a petition explaining why colour is necessary. The USPTO also has the further proviso that the colour drawings are of sufficient quality to enable all details in the drawings to be reproduced in black and white in the printed patent.
Allowing colour drawings in patent applications has long been requested by the patent attorney profession and is a topic on the agenda of the PCT Working Group. Many will hope that the initiative taken by the EPO in this regard will result in widespread adoption of this policy by other patent offices. However, until there is more widespread adoption, where an application with colour drawings is used as the priority document there will be the risk that the conversion to black and white drawings by the patent offices in the jurisdictions of choice will result in the loss of some details and negatively affect the disclosure.
Authors: Quinn Miller and Jim Piper
