Federal Circuit Affirms Judgment Of Patent Claim Indefiniteness
On September 4, 2018, the Court of Appeals for the Federal Circuit (CAFC) issued an opinion affirming a judgment of the United States District Court for the District of Delaware finding a patent claim invalid for indefiniteness. Intellectual Ventures I LLC v. T-Mobile USA, Inc. et al., —F.3d—(Fed. Cir. September 4, 2018). The CAFC ruled that the claim was invalid because it included a limitation that was entirely subjective and user-defined.
A United States utility patent must “conclude with one or more claims particularly pointing out and distinctly claiming the subject matter which the inventor or a joint inventor regards as the invention.” 35 U.S.C. § 112(b). Because the claims define the scope of what is protected by the patent, they must be written so that their limits can be understood “with reasonable certainty” by a hypothetical person of ordinary skill in the technical field of the invention. Nautilus, Inc. v. Biosig Instr., Inc., 134 S. Ct. 2120, 2129 (2014).
In this case, the claim in question was written in means-plus-function form: “allocating means for allocating resources to said IP flow . . . so as to optimize end user application IP QoS [quality-of-service] requirements of said software application.” Such claims are construed to cover the structures described in the specification to perform the recited function, and equivalents of those structures. 35 U.S.C. § 112(f).
The District Court found that this limitation was indefinite. On appeal, Intellectual Ventures argued that the District Court’s judgment was wrong because the specification contained descriptions of structures to perform the recited function specific enough for one of skill in the art to recognize the boundaries of the claim.
The CAFC disagreed. The CAFC ruled that the claimed function (“optimiz[ing] . . . QoS”) is a “term of degree” that is “purely subjective and depends on the unpredictable vagaries of any one person’s opinion”—in other words, that a hypothetical person of skill in the art would not have any way of knowing whether the claimed function is being performed. In response to the patent owner’s argument about the specific structure described in the patent, the CAFC held that the existence of such structure is irrelevant: “We see no error in the district court’s conclusion that . . . because the function is indefinite, there was no need to evaluate structure.”