How should changes to patent drawings be indicated on replacement sheets?

This page is an FAQ based on guidance from the Manual of Patent Examining Procedure. It is provided as guidance, with links to the ground truth sources. This is information only: it is not legal advice.

When submitting replacement sheets for patent drawings, it’s crucial to properly indicate the changes made. The MPEP section 608.02(p) provides specific guidance:

“All changes to the drawings should be explained, in detail, in either the drawing amendment or remarks section of the amendment paper.“

To effectively indicate changes:

• Use a marked-up copy to show all modifications
• Provide detailed explanations in the drawing amendment or remarks section
• Ensure that new matter is not introduced
• Follow the format requirements outlined in 37 CFR 1.121(d)

Proper indication of changes helps examiners quickly understand and review the modifications, potentially speeding up the examination process.