What is considered “well-understood, routine, conventional activity” in patent claims?

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.

“Well-understood, routine, conventional activity” is a key concept in patent eligibility analysis. As explained in MPEP 2106.05(d):

“A factual determination is required to support a conclusion that an additional element (or combination of additional elements) is well-understood, routine, conventional activity.”

The MPEP provides several ways an examiner can support such a conclusion:

• A citation to an express statement in the specification or during prosecution
• A citation to one or more court decisions
• A citation to a publication demonstrating the well-understood, routine, conventional nature of the additional element(s)
• A statement that the examiner is taking official notice

It’s important to note that just because something is disclosed in a piece of prior art does not mean it is well-understood, routine, and conventional. The MPEP states: “The question of whether a particular claimed invention is novel or obvious is ‘fully apart’ from the question of whether it is eligible.”