How does the USPTO weigh evidence of expected and unexpected results in patent applications?

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 weighs evidence of expected and unexpected results in patent applications as follows:

• Evidence of unexpected results must be weighed against evidence supporting prima facie obviousness.
• The strength of each supporting and opposing factor is considered.
• The examiner must make a final determination based on the entirety of the record.

As stated in MPEP 716.02(c):

‘The evidence presented to rebut the prima facie case of obviousness must be commensurate in scope with the claims which the evidence is offered to support.’

This means that the unexpected results must be demonstrated across the full range of the claimed invention.