Are “use” claims ever acceptable in US patent applications?

While “use” claims are generally problematic in US patent applications, there are rare instances where they might be acceptable:

1. Certain process claims: If the claim clearly implies the steps involved, it might be considered definite. However, this is risky and not recommended.
2. Product-by-process claims: These are not strictly “use” claims but can describe a product in terms of the process used to make it.

The MPEP 2173.05(q) states: “Ex parte Dunki, 153 USPQ 678 (Bd. App. 1967) held the following claim to be an improper definition of a process: ‘The use of a high carbon austenitic iron alloy having a proportion of free carbon as a vehicle brake part subject to stress by sliding friction.’ In Clinical Products Ltd. v. Brenner, 255 F. Supp. 131, 149 USPQ 475 (D.D.C. 1966), the following claim was held definite and proper: ‘The use of a sustained release therapeutic agent in the body of ephedrine absorbed upon polystyrene sulfonic acid.’“

Despite these exceptions, it’s generally safer and more effective to draft claims as method or product claims to avoid potential indefiniteness rejections under 35 U.S.C. 112(b).

To learn more:

• use claims
• US patent applications
• acceptable claims
• process claims
• product-by-process claims