When are annotated sheets required for patent drawing changes?

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.

Annotated sheets are required for patent drawing changes in specific circumstances. According to MPEP 608.02(v), annotated sheets are necessary “When changes are to be made in the drawing itself, other than mere changes in reference characters, designations of figures, or inking over lines pale and rough.” However, the MPEP also notes that “Ordinarily, broken lines may be changed to full without a sketch.” This means that substantial changes to the drawing content require annotated sheets, while minor alterations may not.