I. Introduction

Three years ago in BMC Resources Inc. v. Paymentech L.P., 498 F.3d 1373, 1379, 84 USPQ2d 1545 (Fed. Cir. 2007) (74 PTCJ 644, 9/28/07), the U.S. Court of Appeals for the Federal Circuit first clarified the legal standard for infringing use of method claims where each of the steps is not performed by a single entity. Since then, the issue of so-called ‘‘divided infringement’’ has been front and center in many patent cases, as litigants have tested the boundaries of the doctrine, primarily in cases involving business method, internet, and communications-related patents. Two related developments have flowed from this case law. First, several courts have extended the concept of divided infringement to apparatus or system claims, an issue not yet squarely addressed by the Federal Circuit. Second, some courts have more generally considered the standard for infringing use of system claims, an issue for which there is little guidance in the case law. This article explores the recent case law developments in these areas.