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Means-Plus-Function Claim Held Invalid as Indefinite for Failure to Identify Corresponding Structure

06-1350
June 18, 2007

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Last Month at the Federal Circuit - July 2007

Judges: Rader, Archer (author), Gajarsa

[Appealed from: W.D. Wash., Chief Judge Lasnik]

In Biomedino, LLC v. Waters Technologies Corp., No. 06-1350 (Fed. Cir. June 18, 2007), the Federal Circuit affirmed the district court’s judgment that claims 13-17 and 40 of U.S. Patent No. 6,602,502 are invalid for indefiniteness under 35 U.S.C. § 112, ¶ 2.

The claim term at issue was “control means for automatically operating said valving” or valves. The only references in the specification to the “control means” were a box labeled “Control” in Figure 6 and a statement that the regeneration process of the invention “may be controlled automatically by known differential pressure, valving and control equipment.”

The district court noted that if a claim element contains the term “means” and recites a function, as does “control means” in this case, there is a presumption that § 112, ¶ 6 applies. This particular statutory provision permits broad means-plus-function language in the claims, and at the same time, requires that the patent specification disclose some structure that performs the specified function. In the absence of such disclosure, means-plus-function claims are deemed to have failed to particularly point out and distinctly claim the invention as required by the second paragraph of § 112, and will thus be invalid as indefinite.

The district court concluded that inclusion of the word “control” did not identify structure and, thus, did not overcome the presumption that § 112, ¶ 6 applies. Concluding that “[t]he specification says nothing more than that unspecified equipment may be used to control the regeneration process,” the district court held that “[t]he failure to disclose a structure corresponding to the ‘control means’ function makes claims 13-17 and claim 40 of indefinite scope in violation of § 112, ¶ 2 of the Patent Act.” Slip op. at 4.

On appeal, Biomedino, LLC (“Biomedino”) asserted that the term “control” to describe “means” recited sufficient structure well understood by those of skill in the art, obviating the need for § 112, ¶ 6. The Federal Circuit disagreed and noted with approval the district court’s observation that the reference to “control” was simply an adjective describing “means” and did not denote a structure or material capable of performing the identified function. The Court thus concluded that “control means” was a means-plus-function claim limitation under § 112, ¶ 6.

The Federal Circuit first identified the function of the limitation. Here, there was no dispute that the claimed function is “automatically operating said valving” or “automatically operating valves.” The Court then determined whether the specification described a corresponding structure for that function. The parties agreed that the only references in the specification to the “control means” were the box labeled “Control” in Figure 6 and a statement that the regeneration process may be “controlled automatically by known differential pressure, valving and control equipment.” Biomedino argued that there were many known ways to operate valves in the art, including pneumatically, hydraulically, mechanically, and electrically, and that the specification provided adequate guidance for one skilled in the art. This case thus presented the following question: “For purposes of § 112, ¶ 6, is sufficient corresponding structure disclosed when the specification simply recites that a claimed function can be performed by known methods or using known equipment where prior art of record and the testimony of experts suggest that known methods and equipment exist?” Id. at 7-8.

The Federal Circuit considered this issue by looking at two of its earlier decisions regarding § 112, ¶ 6, Med. Instrumentation & Diagnostics Corp. v. Elekta AB, 344 F.3d 1205 (Fed. Cir. 2003), and Atmel Corp. v. Info. Storage Devices, Inc., 198 F.3d 1374 (Fed. Cir. 1999). In Medical Instrumentation, the Federal Circuit disagreed with the district court’s identification of software as a corresponding structure for § 112, ¶ 6 because software was not clearly linked in the specification or prosecution history to the claimed function. In Atmel, the Federal Circuit found that an article title in the specification disclosed sufficient structure because “the article’s title alone was sufficient to indicate to one skilled in the art the precise structure of the means recited in the specification.” Slip op. at 9. Accordingly, the Federal Circuit concluded that the district court improperly granted SJ that the patent was invalid for indefiniteness.

In the present case, the Federal Circuit found nothing to suggest a structure for the claimed control means. The Federal Circuit explained that while the patentee need not disclose details of structures well known in the art, the specification must nonetheless disclose some structure. “The inquiry is whether one of skill in the art would understand the specification itself to disclose a structure, not simply whether that person would be capable of implementing a structure.” Id. at 11. The Federal Circuit thus affirmed the district court’s indefiniteness holding.