Opinion ID: 209426
Heading Depth: 4
Heading Rank: 1

Heading: Claim Construction of “controlling”

Text: Invacare challenges the district court’s construction of the “controlling” step in claim 29 of the ’517 patent, which the district court declined to interpret as a step-plusfunction limitation under 35 U.S.C. § 112 ¶ 6. Claim Construction Order at 34-35. The “controlling” step reads: controlling a pressure of the flow of breathing gas delivered to a patient based on a product of the expiratory gain and the fluid characteristic during at least a portion of an expiratory phase of such a patient’s breathing cycle, so that a pressure of the flow of breathing gas delivered to the patient during at least a portion of the expiratory phase varies with fluctuations of the fluid characteristic. Without pointing to anything in the claim language itself that would dictate construction under § 112 ¶ 6, Invacare relies entirely on the prosecution history. Specifically, Invacare asserts that Respironics urged the examiner to interpret the “controlling” step as a step-plus-function limitation and that the examiner adopted this interpretation. Neither assertion is persuasive. First, Respironics never urged the examiner to apply § 112 ¶ 6 to method claim 29 (then-claim 73). When that claim was added during prosecution, together with 2008-1164, -1193 16 apparatus claim 24 (then-claim 68), the pending application already included apparatus claim 1 (then-claim 45) and method claim 9 (then-claim 53). J.A. 3790-801. Both apparatus claims recite a “processing means . . . for producing a command signal,” and both method claims recite “controlling a pressure of the flow of breathing gas delivered to a patient.” Notably, the apparatus limitations are written in “means for” format; by contrast, the method steps lack the words “step for,” thus triggering a presumption that § 112 ¶ 6 does not apply to the method steps. See Generation II Orthotics Inc. v. Med. Tech. Inc., 263 F.3d 1356, 1368 (Fed. Cir. 2001) (stating that “there is a presumption that . . . limitations are not subject to section 112, paragraph 6” when they do not use the words “means for” or “step for”). When Respironics added new claims 68 and 73 (now 24 and 29, respectively), Respironics told the examiner that “[n]ew independent claims 68 and 73 are similar to existing independent claims 45 and 53” (now 1 and 9, respectively). J.A. 3788. Although Invacare now seizes upon Respironics’s “similar to” language in this statement, it is clear, based on the above comparison of common terms, that Respironics was referring to the common language used respectively in the two apparatus claims (“processing means . . . for producing a command signal”) and in the two method claims (“controlling a pressure of the flow of breathing gas delivered to a patient”), not to any alleged similarity between apparatus and method claims. Thus, contrary to Invacare’s assertion, Respironics did not urge the examiner to import a meaning under § 112 ¶ 6 from the apparatus claims into the method claims. Second, the examiner never adopted any step-plus-function interpretation. In the reasons for allowance, the examiner set forth the various limitations of the apparatus claims, referring to the “processing means” limitation in the apparatus claims, but not 2008-1164, -1193 17 the “controlling” step in the method claims. J.A. 3806. After setting forth the apparatus limitations, the examiner referred to the “abovementioned” (apparatus) limitations only as “means plus function” limitations. Id. (emphasis added). Nowhere in the reasons for allowance does the examiner mention the patent’s “controlling” steps, or refer to them as step-plus-function limitations. Accordingly, we reject Invacare’s argument that the prosecution history compels a different construction.