The United States Court of Appeals for the Federal Circuit recently issued a ruling vacating a district court’s grant of summary judgment of non-infringement because the district court erred in its claim construction analysis. See Intellectual Ventures I LLC v. T-Mobile USA, Inc., Nos. 2017-2434, 2017-2435 (Fed. Cir. Sept. 4, 2018) (Before Prost, Chief Judge, Moore and Reyna, Circuit Judges) (Opinion for the court, Moore, Circuit Judge).

The case began when Intellectual Ventures I LLC (“IV”) sued T-Mobile USA, Inc. (“T-Mobile”) for infringing U.S. Patent No. 6,640,248 (the ’248 patent). The ’248 patent describes “an application-aware resource allocator” that allocates bandwidth resources to transmit information from software applications over a packet-switched network. It describes the application-aware resource allocator with reference to the seven-layer Open Systems Interface networking protocol stack standard (“OSI standard”), which includes a “physical layer” at layer 1, a “data link layer” at layer 2, a “network layer” at layer 3, a “transport layer” at layer 4, and an “application layer” at layer 7.

IV and T-Mobile disputed construction of “application-aware resource allocator” in claim 1 and “application-aware media access control (MAC) layer” in claim 20. IV offered a construction requiring that the resource allocator “allocate[] resources based on application type.” Under IV’s construction, the application type could be discerned by the resource allocated using information obtained from any of the network layer 3, the transport layer 4, and the application layer 7. In contrast, T-Mobile offered a construction requiring that the resource allocator not only “ha[ve] knowledge of the type of data application,” but that it “further take[] into account, when allocating bandwidth, information about applications at [OSI] application layer 7.” The district court adopted T-Mobile’s construction of “application-aware resource allocator.” It noted that this construction was “supported by the prosecution history, during which the patentee distinguished its invention from prior art based on the fact that the invention is ‘aware of layer 7 application information’ and, further, that the resource allocator must ‘be able to take into account, when allocating bandwidth, information at . . . layer 7.”

The parties also disputed the construction of the means-plus function claim language “allocating means for allocating resources to said IP flow . . . so as to optimize end user application IP [quality of service (“QoS”)] requirements of said software application.” IV argued the function was “allocating resources to said IP flow . . . so as to optimize end user application IP QoS requirements of said software application.” T-Mobile countered that the function was indefinite, and the district court agreed.

Following claim construction, T-Mobile moved for summary judgment of non-infringement. The district court granted T-Mobile’s motion, stating “IV’s opposition to summary judgment depends entirely on a claim construction position the Court has rejected.” IV appealed the grant of T-Mobile’s motion for summary judgment, arguing the district court erred in its construction of “application-aware resource allocator” and indefiniteness determination for “allocating means.”

First, the Court addressed the term “application-aware resource allocator.” According to IV, application awareness requires only that the resource allocator allocate resources based on application type, which can be discerned using information obtained from any of network layer 3, transport layer 4, or application layer 7. The Court agreed, explaining that the plain language of claims 1 and 20 do not specify how the resource allocator becomes “aware” of an application. For example, the plain language of the claims did not require that the resource allocator use information obtained from application layer 7. Additionally, some embodiments described in the specification did not describe the resource allocator using information from application layer 7. The Court explained that statements in the ’248 patent’s prosecution history say only that “application awareness” means being aware of applications running at application layer 7, but did not require the resource allocator to use data obtained from application layer 7 when allocating resources.

The Court then rejected T-Mobile’s argument that statements made in the prosecution history of the ’248 patent disavowed the full scope of the claims. Disavowal is an “exacting” standard under which it must be established that the patentee “demonstrate[d] an intent to deviate from the ordinary and accustomed meaning of a claim term” through “expressions of manifest exclusions or restriction, representing a clear disavowal of claim scope.” Epistar Corp. v. Int’l Trade Comm’n, 566 F.3d 1321, 1334 (Fed. Cir. 2009). The statements T-Mobile cited only say that “application awareness” means being aware of applications running at application layer 7, which does not meet the exacting standard from Epistar.

The Court also emphasized that in the same portion of the prosecution history pointed to by T-Mobile as limiting allocation to information obtained from application layer 7, the patent owner added a dependent claim that permitted the allocation to be based on information from network layer 3, transport layer 4, or application layer 7. According to the Court, this evidenced that the patent owner knew how to limit the scope of the claim to allocation based only on application layer 7 (or other layers), but because the patent owner chose not to do so in the independent claim, there was no disavowal.

Having found no disavowal, the Court held that the “application-aware resource allocator” in claim 1 and “application-aware media access control (MAC) layer” in claim 20 were not restricted to allocating resources using information obtained from application layer 7. Thus, the district court erred in its construction of these terms.

Next, the Court turned to the indefiniteness issue, and affirmed the district court’s determination that the claimed “allocating means for allocating resources to said IP flow . . . so as to optimize end user application IP QoS requirements of said software application” is indefinite. Under 35 U.S.C. § 112, a patent claim must “particularly point[] out and distinctly claim[] the subject matter” regarded as the invention. While a claim employing a “term[] of degree” may be definite “where it provide[s] enough certainty to one of skill in the art when read in the context of the invention,” Interval Licensing LLC v. AOL, Inc., 766 F.3d 1364, 1370 (Fed. Cir. 2014), a term of degree that is “purely subjective” and depends “on the unpredictable vagaries of any one person’s opinion” is indefinite. Datamize, LLC v. Plumtree Software, Inc., 417 F.3d 1342, 1350-51 (Fed. Cir. 2005). According to the ’248 patent’s own terms, “optimiz[ing] . . . QoS” is a “term of degree,” which is “entirely subjective and user-defined.” Simply understanding that “optimiz[ing] . . . QoS” relates to the end-user experience “fails to provide one of ordinary skill in the art with any way to determine whether” QoS has been “optimiz[ed].” Consequently, the Court found no error in the district court’s conclusion that this function is indefinite. Further, because it found the function of this means-plus-function limitation indefinite, it did not need to consider whether the specification disclosed sufficient structure for this limitation. Therefore, the Court affirmed the district court’s holding for this term.

Because the district court’s grant of summary judgment of non-infringement resulted from an improper construction of “application aware resource allocator,” the Court vacated and remanded.

Take Away

In claim construction analyses, the plain and ordinary meaning of a claim term will not be narrowed by statements in the prosecution history, unless those statements clearly and explicitly evidence the patentee’s intent to depart from the full scope of the claim. If a dependent claim includes the purportedly disclaimed subject matter and was added at the time of the purportedly disavowing statements, a finding of disavowal is unlikely. Furthermore, a means-plus-function term should clearly and objectively define the function of the limitation; if the function is a subjective term of degree, a finding that the term is indefinite is likely.

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