How are differences between the claimed design and prior art evaluated?

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 evaluating differences between the claimed design and prior art for nonobviousness, the MPEP emphasizes that it’s the overall appearance that matters:

“In determining patentability under 35 U.S.C. 103, it is the overall appearance of the design that must be considered. See In re Leslie, 547 F.2d 116, 192 USPQ 427 (CCPA 1977).”

The MPEP further states:

• “The mere fact that there are differences between a design and the prior art is not alone sufficient to justify patentability.”
• “All differences between the claimed design and the closest prior art reference should be identified in any rejection of the design claim under 35 U.S.C. 103.”
• “If any differences are considered de minimis or inconsequential from a design viewpoint, the rejection should so state.”

This guidance emphasizes that examiners must consider the overall visual impression of the design, identify all differences from the prior art, and evaluate whether these differences would be obvious to a designer of ordinary skill in the art.