How does the concept of “teaching away” apply in patent obviousness cases?

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.

“Teaching away” is a concept in patent law that can be used to rebut a prima facie case of obviousness. According to MPEP 2144.05:

“A prima facie case of obviousness may also be rebutted by showing that the art, in any material respect, teaches away from the claimed invention.”

Teaching away occurs when a person of ordinary skill, upon reading the reference, would be discouraged from following the path set out in the reference, or would be led in a direction divergent from the path that was taken in the claim.

However, the mere disclosure of alternative options does not constitute teaching away. As stated in the MPEP:

“[T]he prior art’s mere disclosure of more than one alternative does not constitute a teaching away from any of these alternatives because such disclosure does not criticize, discredit, or otherwise discourage the solution claimed.”

To establish that a reference teaches away, applicants need to show that the reference would discourage or criticize the claimed invention.