Opinion ID: 814601
Heading Depth: 1
Heading Rank: 4

Heading: means-plus-function claiming

Text: Means-plus-function limitations are governed by 35 U.S.C. § 112, ¶ 6, which allows a patentee to express a claimed element as a “means or step for performing a specified function without the recital of structure, material, or acts in support thereof.” Such an element “shall be construed to cover the corresponding structure, material, or acts described in the specification and equivalents thereof.” § 112, ¶ 6. The statute thus establishes a quid pro quo whereby a patentee may conveniently claim an element using a generic “means” for performing a function, provided the patentee’s specification discloses structure capable of performing that function. Atmel Corp. v. Info. Storage Devices, Inc., 198 F.3d 1374, 1381 (Fed. Cir. 1999). Whether a claim limitation invokes means-plusfunction claiming under § 112, ¶ 6, is a matter of claim construction and therefore a question of law that we review without deference. See Cybor Corp. v. FAS Techs., Inc., 138 F.3d 1448, 1454–55 (Fed. Cir. 1998) (en banc). Our first step in analyzing a means-plus-function limitation is to determine whether § 112, ¶ 6, applies. Kemco Sales, Inc. v. Control Papers Co., 208 F.3d 1352, 1361 (Fed. Cir. 2000). We start by considering whether 8 LIGHTING BALLAST v. PHILIPS ELECTRON the limitation includes the word “means,” “as the terms ‘means’ and ‘means for’ have become closely associated with means-plus-function claiming.” Inventio AG v. Thyssenkrupp Elevator Ams. Corp., 649 F.3d 1350, 1356 (Fed. Cir. 2011). The word “means” triggers a presumption that “the inventor used this term advisedly to invoke [means-plus-function claiming].” York Prods., Inc. v. Central Tractor, 99 F.3d 1568, 1574 (Fed. Cir. 1996) (citation omitted). The presumption triggered by use of the word “means” may be rebutted if the claim itself recites sufficient structure for performing the function. See Cole v. Kimberly-Clark Corp., 102 F.3d 524, 531 (Fed. Cir. 1996). In Cole, for example, we construed a claim directed to removable training pants for toddlers. 102 F.3d at 529. The claim recited a “perforation means extending from the leg band means to the waist band means through the outer impermeable layer means for tearing the outer impermeable layer means for removing the training brief in case of an accident by the user.” Id. at 530. We held that the term “perforation means” did not invoke meansplus-function claiming because the claim described not only the structure for performing the tearing function (“perforation”) but also the structure’s location (extending from the leg band to the waist band) and extent (extending through the outer impermeable layer). Id. at 531. “An element with such a detailed recitation of its structure, as opposed to its function, cannot meet the requirements of [§ 112, ¶ 6].” Id. By contrast, when a term only indicates what the recited means “does, not what it is structurally,” the claim is properly construed under § 112, ¶ 6. Laitram Corp. v. Rexnord, Inc., 939 F.2d 1533, 1536 (Fed. Cir. 1991). For example, in Biomedino, we construed the phrase “control means for automatically operating said valving.” 490 F.3d at 949. We held that the term “control” failed to convey sufficient structure to rebut the presumption that LIGHTING BALLAST v. PHILIPS ELECTRON 9 means-plus-function claiming applied because “‘control’ is simply an adjective describing ‘means’: it is not a structure or material capable of performing the identified function.” Id. at 950. Here, because claim 1 of the ’529 Patent recites a “voltage source means,” we start from the presumption that means-plus-function claiming under § 112, ¶ 6, applies. The claim goes on to recite the corresponding function: “providing a constant or variable magnitude DC voltage between the DC input terminals.” The term “voltage source” implies that voltage is provided, but the claim only sets out an indication of what the element “does, not what it is structurally.” Laitram, 939 F.2d at 1536. The recited function implies no more structure than the term “voltage source” itself. While “DC input terminals” is a structural term, the input terminals receive rather than provide DC voltage. Thus, the claim does not contain structural language that is sufficient to remove “voltage source means” from the reach of § 112, ¶ 6. In some circumstances, expert testimony may be probative of whether a claim term itself corresponds to sufficiently definite structure. In Rembrandt Data Techs., LP v. AOL, for example, we relied on expert testimony to confirm that the terms “fractional rate encoding” and “trellis rate encoding” were commonly used in publications to identify defined algorithms (i.e., structure) known in the art. 641 F.3d 1331, 1340–41 (Fed. Cir. 2001). Because the terms were “self-descriptive,” we held that the terms “fractional rate encoding means” and “trellis encoding means” were not governed by § 112, ¶ 6, notwithstanding the word “means.” Id. at 1340–41. Lighting Ballast relies on expert testimony to support its argument that “voltage source means” implies structure and, as a result, means-plus-function claiming does not apply. Dr. Roberts, Lighting Ballast’s expert, testified 10 LIGHTING BALLAST v. PHILIPS ELECTRON that “[t]he ‘voltage source’ limitation connotes, or suggests, to me, and would connote to anyone skilled in the art, the structure of a rectifier. . .” because “the only way for a [l]ighting [b]allast to convert AC (from a ‘power line source’ such as a wall outlet or other similar AC power source in a home or office) into DC (for use at the ‘DC supply voltage’) is through a rectifier.” Joint App. 21. Dr. Roberts also stated that a battery could be used as the “voltage source means” if a DC power source was used. Id. at 21–22. Lighting Ballast’s expert testimony suggests that some structure for performing the recited function is implied, but it does not cure the absence of structural language in the claim itself. Nor does the testimony establish that the term “voltage source” was used synonymously with a defined class of structures at the time the invention was made, unlike the testimony in Rembrandt. See id. at 1341. In fact, Lighting Ballast’s record testimony suggests a lack of a defined class of structures. While a rectifier and a battery may be examples of structures that commonly perform the recited function, there are many other ways to provide DC voltage, including “generators” and “solar voltaic cells,” as Lighting Ballast’s expert admitted. Joint App. 1623. Lighting Ballast points to case law in which this Court declined to apply means-plus-function claiming in view of expert testimony and other extrinsic evidence showing that certain claimed elements implied sufficient structure. In those cases, however, we started from the presumption that means-plus-function claiming did not apply because the claim limitations at issue did not include the word “means.” See MIT v. Abacus Software, 462 F.3d 1344, 1353 (Fed. Cir. 2006) (“The phrase ‘colorant selection mechanism’ is presumptively not subject to 112 ¶ 6 because it does not contain the term ‘means.’”); Lighting World, Inc. v. Birchwood Lighting, Inc., 382 F.3d 1354, 1359 (Fed. Cir. 2004) (“Because the ‘connector LIGHTING BALLAST v. PHILIPS ELECTRON 11 assembly’ limitation does not contain the term ‘means,’ we begin with the presumption that section 112 ¶ 6 does not apply to that limitation.”); Apex Inc. v. Raritan Computer, Inc., 325 F.3d 1364, 1372 (Fed. Cir. 2003) (“As an initial matter, none of the claim limitations asserted by Raritan to be means-plus-function limitations contains the term ‘means,’ which, as noted, is central to the analysis.”); Greenberg v. Ethicon Endo-Surgery, Inc., 91 F.3d 1580, 1583 (Fed. Cir. 1996) (construing the term “detent mechanism”; “means” did not appear in the claim.). In this case, we start with the presumption that means-plusfunction claiming does apply because the claim limitation includes the word “means.” ULT failed to present sufficient evidence to overcome that presumption.