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Functional Claim Elements Must Be Backed by Sufficient Structural Guidance

By Asher Lowenstein – Edited by Mengyi Wang Robert Bosch, LLC, v. Snap-On Inc., 2014-1040 (Fed. Cir. Oct. 14, 2014) Slip Opinion The Federal Circuit affirmed a district court decision that patent claims without reference to structure are indefinite under 35 U.S.C. § 112(f). The dispute involved Bosch’s patent—U.S. Patent No. 6,782,313 (“the ’313 patent”)—which claims “a diagnostic tester that determines whether the computerized control unit in a motor vehicle needs to be reprogrammed.” Slip op. at 2.  Bosch sued Snap-On for infringing the ’313 patent, and Snap-on countered by arguing that the two claim terms “program loading device” and “program recognition device” are means-plus-function terms that fall within the purview § 112 and are indefinite. Id. at 4. The U.S. District Court for the Eastern District of Michigan agreed with Snap-on. Id. On appeal,  while disagreeing with the district court that any use of the word “means” invokes § 112(f), id. at 7, the Federal Circuit affirmed that the patent claims were indefinite. Id. at 12. In patent applications, it is often easiest to describe an invention as something to be used as a means for a particular function. After the Supreme Court in Halliburton Oil Well Cementing Co. v. Walker found such descriptions invalid, § 112(f) was specifically added to allow these formulations with some limitations. 329 U.S. 1, 9 (1946) hosted by “Congress decided to permit broad means-plus-function language, but provided a standard to make the broad claim language more definite.” Valmont Indus., Inc. v. Reinke Mfg. Co., Inc., 983 F.2d 1039, 1042 (Fed. Cir. 1993) hosted by The limitations are that “[t]he applicant must describe in the patent specification some structure which performs the specified function,” and the court must relate the language to the corresponding structure. Id.The Federal Circuit refers to this as a “two-step process.” Slip op. at 4. First, the court determines whether the claim is drafted in a means-plus-function format, thus invoking § 112(f). Id. If the court concludes that the claim invokes § 112(f), it proceeds to the next step and attempts to construe the term by identifying corresponding structures. Id. at 5. With respect to Bosch’s claims, the court went through both steps using essentially the same analysis. Under the first step the court found that the patent’s specifications did “not contain a single reference to the structure,” id. at 9, and “provide no structural guidance . . . [and] are solely functional,” id. at 10. Therefore, the terms invoke § 112(f). Id. at 12. Proceeding to the second step, the court found it could not construe the terms by identifying corresponding structures because “as already discussed . . . the specification . . . offers no further guidance about their structures.” Id. This application of the two-step process suggests that there is really only one question: whether the claim terms refer to structural elements. It can be unclear whether a term is considered a structural or functional description. The court has found that a term such as “circuit” is a “structure-connoting term” for which § 112(f) presumptively does not apply. Linear Tech. Corp. v. Impala Linear Corp., 379 F.3d 1311, 1320 (Fed. Cir. 2004) hosted by  Similarly, the court held that “modernizing device” is a term “connot[ing] sufficiently definite structure.” Inventio AG v. Thyssenkrupp Elevator Ams. Corp., 649 F.3d 1350, 1361 (Fed. Cir. 2011). In Bosch, however, the court held that “the claims involve ordinary functional terms, and there is no language . . . that defines the terms to refer to structures.” Slip. op. at 10–11. Patent filers have adapted terms used in claims to avoid invoking § 112(f). Patently-O observes that, whereas twenty years ago most claims used means-plus-function formulations, fewer than five percent do so now. Based on Bosch, Monday Morning Prosecutor suggests including examples of hardware components to make claims more definite. However, it may suffice simply to include a more technical term that could be seen as a “structure-connoting term” rather than a “solely functional” term. IP Blitz and Medical Device Patent Counsel feature further practical implications from the ruling.