Chapter IX – Drawings
10. Amendments to drawings
Amendments are permitted to the drawings, as well as to the other documents. These amendments may be made at the request of the party concerned or of the EPO. The amendments may concern either clerical errors or more substantial changes.
Amendments to drawings are, in general, subject to the same rules as apply in respect of amendments to other application documents and therefore do not require further analysis here. See also A‑III, 16, A‑V, 2, B‑XI, 8, C‑III, 2, C‑IV, 5, Part H, in particular H‑II, 2 and H‑III, 2.
The general rule governing the admissibility of amendments, which the examiner must always bear in mind, is that they must not extend the content of the application as filed, i.e. they must not have the effect of introducing new material.
If drawings that depart substantially from the physical requirements laid down in the Implementing Regulations are filed to establish a particular date of filing or retain a priority date, the Receiving Section will permit them to be amended or replaced to provide drawings complying with the Implementing Regulations, provided that it is clear that the amendments do not introduce new material into the application. In view of this proviso, applicants should take care that any "informal" drawings filed clearly show all the features necessary to illustrate the invention.