How does the USPTO evaluate unexpected results for a genus claim?

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.

The USPTO evaluates unexpected results for a genus claim by considering whether the evidence presented is representative of the entire claimed genus. The MPEP 716.02(d) provides guidance:

The nonobviousness of a broader claimed range can be supported by evidence based on unexpected results from testing a narrower range if one of ordinary skill in the art would be able to determine a trend in the exemplified data which would allow the artisan to reasonably extend the probative value thereof.

This means that while testing every species within a genus is not always necessary, the evidence should show a trend that a skilled artisan could reasonably extend to the entire genus. The USPTO will consider whether the provided data is sufficient to conclude that the unexpected results would occur across the entire scope of the genus claim.