How can I determine if a trademark or trade name in a patent claim is indefinite?

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.

To determine if a trademark or trade name in a patent claim is indefinite, consider the following factors:

• Whether the trademark or trade name is used to identify or describe a particular material or product.
• If it’s used as a limitation to identify or describe a particular material or product, it may render the claim indefinite.
• The scope of the trademark or trade name may change over time, leading to uncertainty in claim interpretation.

As stated in MPEP 2173.05(u):

“If the trademark or trade name is used in a claim as a limitation to identify or describe a particular material or product, the claim does not comply with the requirements of the 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph.“

Examiners should carefully evaluate the use of trademarks or trade names in claims to ensure clarity and definiteness.