IP Law Daily PTAB failed to adopt broadest reasonable construction in IPR of Network-1 patents
Monday, March 26, 2018

PTAB failed to adopt broadest reasonable construction in IPR of Network-1 patents

By Cheryl Beise, J.D.

The Patent Trial and Appeal Board erred by construing a key claim term too narrowly during inter partes reviews of four patents owned by Network-1 Technologies, the U.S. Court of Appeals for the Federal Circuit has held. The Board’s findings that dozens of challenged claims were neither obvious nor anticipated were reversed. On remand, the Board was directed to adopt petitioner Google’s proposed construction of the claim term "non-exhaustive search." However, the Board’s findings were not disturbed as to the Board’s findings regarding four patent claims that Google did not challenge on appeal (Google LLC v. Network-1 Technologies, Inc., March 26, 2018, Schall, A.).

Network-1 Technologies, Inc., owns U.S. Patent Nos. 8,640,179 ("the ’179 patent"); 8,205,237 ("the ’237 patent"); 8,010,988 ("the ’988 patent"); and 8,656,441("the ’441 patent"). After Network-1 filed an infringement suit against Google, Google petitioned for inter partes review (IPR) of several claims of the patents. In four separate final decisions, the PTAB concluded that Google failed to demonstrate either anticipation under 35 U.S.C. §102 or obviousness under 35 U.S.C. §103 with respect to most of the reviewed claims. Google appealed the majority of the PTAB’s findings, and the Federal Circuit consolidated the cases.

For purposes of the appeal, the parties agreed that claim 1 of the ’179 patent is representative of all the claims at issue and that the written description of the ’179 patent is representative. The ’179 patent relates to identifying a work, such as a digital audio or video file, without the need to modify the work. The parties further agreed that the correct construction of "non-exhaustive search," as it appears in claim 1 of the ’179 patent, would dispose of the claim construction issue in all four of the patents-in-suit.

Claim construction. The ’179 patent’s written description does not refer to "exhaustive" or "non-exhaustive" searches and nowhere identifies the types of searches that fall into either category. Google proposed to construe the term "non-exhaustive search" as "a search that locates a match without conducting a brute force comparison of all possible matches, and all data within all possible matches." The Board rejected Google’s construction in favor of the construction proposed by Network-1: "a search that locates a match withouta comparison of all possible matches." Based upon that construction, the Board determined that Google had failed to demonstrate that the cited prior art rendered the challenged claims of the ’179 patent unpatentable as either anticipated or obvious.

The parties agreed that the Board was required by its rules to apply the broadest reasonable construction of the term "non-exhaustive search" in light of the patents’ specifications. Although Google’s construction of the word "exhaustive" was narrower than the Board’s, the Federal Circuit found that that Google’s construction of the term "non-exhaustive search" was actually broader because it necessarily encompassed all of the searches covered by the Board’s construction. The Board’s construction, on the other hand, did not necessarily encompass all of the searches covered by Google’s construction.

The next question was whether Google’s narrower construction of "exhaustive"—and hence its broader construction of "non-exhaustive"—was "reasonable." Contrary to Network-1’s contention, the specification of the ’179 patent did not suggest the narrower construction of "non-exhaustive search." The portions of the specification cited by Network-1 did not draw a clear line between "exhaustive" and "non-exhaustive" searching in terms of how much data within a record a search must consider in order to qualify as one or the other. The prosecution history provided no additional guidance.

Regarding the extrinsic evidence, Network-1 presented to the Board a Wikipedia entry describing a "brute force search." However, the entry did not address whether or not a "brute force search" examines all data within a possible match, the court observed. Network-1 also cited the testimony of its expert witness, but this evidence was not before the Board when it first construed the term in its institution decision, and the Board did not mention the testimony when it decided not to modify its original construction.

The court viewed both the intrinsic and extrinsic evidence regarding the meaning of the foundational claim term "exhaustive" to be inconclusive as to the broader or narrower construction of the limitation "non-exhaustive search." Under the circumstances, the Federal Circuit found Google’s construction to be reasonable. "[W]ithout considering all data within all possible matches, a search of features is not guaranteed to find an existing match or a near-match, or it may stop prematurely before finding one," the court explained.

Because under the broadest reasonable construction standard, Google’s proposed construction of the term "non-exhaustive search" was broader, the Board erred in not adopting it. The Board’s decisions were vacated, and the case was remanded for consideration of patentability based upon the correct claim construction. However, the Board’s decisions regarding three independent claims of the ’237 patent and one dependent claim of the ’988 patent were not vacated because they were not challenged on appeal.

The case is Nos. 2016-2509, 2016-2510, 2016-2511, and 2016-2512.

Attorneys: Dan L. Bagatell (Perkins Coie LLP) for Google LLC. Gregory S. Dovel (Dovel & Luner, LLP) for Network-1 Technologies, Inc.

Companies: Google LLC; Network-1 Technologies, Inc.

MainStory: TopStory Patent TechnologyInternet FedCirNews

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