MPEP 2173.05(p)
Claim Directed to Product-By- Process or Product and Process

This is the Ninth Edition of the MPEP, Revision 08.2017, Last Revised in January 2018

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2173.05(p)    Claim Directed to Product-By- Process or Product and Process [R-08.2017]

There are many situations where claims are permissively drafted to include a reference to more than one statutory class of invention.


A product-by-process claim, which is a product claim that defines the claimed product in terms of the process by which it is made, is proper.Purdue Pharma v. Epic Pharma, 811 F.3d 1345, 1354, 117 USPQ2d 1733, 1739 (Fed. Cir. 2016); In re Luck, 476 F.2d 650, 177 USPQ 523 (CCPA 1973); In re Pilkington, 411 F.2d 1345, 162 USPQ 145 (CCPA 1969); and In re Steppan, 394 F.2d 1013, 156 USPQ 143 (CCPA 1967). A claim to a device, apparatus, manufacture, or composition of matter may contain a reference to the process in which it is intended to be used without being objectionable under 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph, so long as it is clear that the claim is directed to the product and not the process.

An applicant may present claims of varying scope even if it is necessary to describe the claimed product in product-by-process terms. Ex parte Pantzer, 176 USPQ 141 (Bd. App. 1972).


A single claim which claims both an apparatus and the method steps of using the apparatus is indefinite under 35 U.S.C. 112(b) or pre-AIA 35 U.S.C. 112, second paragraph. See In re Katz Interactive Call Processing Patent Litigation, 639 F.3d 1303, 1318, 97 USPQ2d 1737, 1748-49 (Fed. Cir. 2011). In Katz, a claim directed to "[a] system with an interface means for providing automated voice messages…to certain of said individual callers, wherein said certain of said individual callers digitally enter data" was determined to be indefinite because the italicized claim limitation is not directed to the system, but rather to actions of the individual callers, which creates confusion as to when direct infringement occurs. Katz, 639 F.3d at 1318 (citing IPXL Holdings v., Inc., 430 F.3d 1377, 1384, 77 USPQ2d 1140, 1145 (Fed. Cir. 2005), in which a system claim that recited "an input means" and required a user to use the input means was found to be indefinite because it was unclear "whether infringement … occurs when one creates a system that allows the user [to use the input means], or whether infringement occurs when the user actually uses the input means."); Ex parte Lyell, 17 USPQ2d 1548 (Bd. Pat. App. & Inter. 1990) (claim directed to an automatic transmission workstand and the method of using it held ambiguous and properly rejected under 35 U.S.C. 112, second paragraph).