Partial structures of chemical compounds in patent claims are not automatically considered indefinite. The MPEP 2173.05(t) provides guidance on this matter: “A claim to a chemical compound is not indefinite merely because a structure is not presented or because a partial structure is presented.” This approach is exemplified in the case of In re Fisher,…

No, a chemical compound claim is not automatically considered indefinite if a complete structure is not presented. The MPEP 2173.05(t) clarifies this point: “A claim to a chemical compound is not indefinite merely because a structure is not presented or because a partial structure is presented.” This guidance is based on court decisions, such as…