Network-1 Technologies, Inc. v. Google LLC

Case: 24-1893 Document: 69 Page: 1 Filed: 04/23/2026

NOTE: This disposition is nonprecedential.

United States Court of Appeals

for the Federal Circuit

______________________

NETWORK-1 TECHNOLOGIES, INC.,

Plaintiff-Appellant

v.

GOOGLE LLC, YOUTUBE, LLC,

Defendants-Appellees

______________________

2024-1893, 2024-1948

______________________

Appeals from the United States District Court for the

Southern District of New York in No. 1:14-cv-09558-PGG-

SN, Judge Paul G. Gardephe.

______________________

Decided: April 23, 2026

______________________

BRIAN DAVID LEDAHL, Russ August & Kabat, Los

Angeles, CA, argued for plaintiff-appellant. Also

represented by MARC A. FENSTER.

ANDREW V. TRASK, Williams & Connolly LLP,

Washington, DC, argued for defendants-appellees. Also

represented by XUN LIU; KEVIN HARDY, Quinn Emanuel

Urquhart & Sullivan, LLP, Washington, DC.

______________________

Case: 24-1893 Document: 69 Page: 2 Filed: 04/23/2026

2 NETWORK-1 TECHNOLOGIES, INC. v. GOOGLE LLC

Before MOORE, Chief Judge, LOURIE and REYNA, Circuit

Judges.

LOURIE, Circuit Judge.

Network-1 Technologies, Inc. (“Network-1”) filed suit

in the United States District Court for the Southern

District of New York, asserting that two separate versions

of Google LLC and YouTube, LLC’s (collectively, “Google”)

Content ID system infringed several claims of its U.S.

Patents 8,010,988 (“the ’988 patent”), 8,205,237 (“the ’237

patent”), 8,904,464 (“the ’464 patent”) (collectively, “the

asserted patents”). Network-1 Techs., Inc. v. Google LLC,

No. 14-cv-PGG-02396, 2024 WL 1814296 (S.D.N.Y. Apr.

24, 2024) (“Decision”). The district court issued a combined

claim construction and summary judgment decision. Id.

The court first determined that the asserted claims of the

’988 and ’464 patents are invalid as indefinite. Id. at *1. It

then determined that neither version of Google’s Content

ID system infringed the asserted claims of the ’237 patent

as a matter of law and thus Google was entitled to

summary judgment of noninfringement as to that patent.

Id.

Because a genuine issue of material fact exists as to

whether one version of Content ID infringes the ’237

patent, we reverse and remand as to that issue. We affirm

the district court’s conclusion of invalidity of the ’988 and

’464 patents for indefiniteness and grant of summary

judgment of noninfringement of the ’237 patent as to the

other version of Content ID.

BACKGROUND

I

Network-1 owns the asserted patents, which are

directed to methods for “linking traditional media to new

interactive media, such as that provided over the internet,”

and “identifying a work . . . without the need to modify the

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NETWORK-1 TECHNOLOGIES, INC. v. GOOGLE LLC 3

work.” See ’988 patent col. 1 ll. 23–28. 1 As an example, the

patent describes “[c]ommerce opportunities” where

television viewers could “place[] . . . direct orders for

products” they see on screen via an “interactive capability,”

i.e., an internet link to a website associated with the

specific product. Id. at col. 1 ll. 36–60. The asserted

patents facilitate this process by describing a technique for

identifying work (such as content or an advertisement)

without inserting an identification code, such as a bar code.

See id. at col. 1 ll. 25–28, col. 3 ll. 8–23, col. 4 ll. 7–19.

In relevant part, claims 15 and 17 of the ’988 patent

and claim 1 of the ’464 patent recite a method comprising

identifying an electronic work or correlating an electronic

work with an identifier via a “non-exhaustive search.” See

’988 patent col. 25 l. 65–col. 26 l. 6; ’464 patent col. 24 ll.

44–49.

In relevant part, independent claim 33 of the ’237

patent recites “[a] computer-implemented method

comprising . . . [a] determin[ation] by the computer

system, an identification of [a] media work using the media

work extracted features to perform a sublinear

approximate-nearest neighbor search of reference

extracted features of reference identified media works.”

’237 patent col. 28 ll. 5, 10–14 (emphasis added).

Google operates the website YouTube, which allows

users to upload content to the internet to be viewed by the

public. Decision, 2024 WL 1814296 at *3. Google employs

a “Content ID” system that allows content owners (e.g.,

copyright owners) to control how their content is used on

YouTube. Id. at *4. The Content ID system generates

matches by comparing an uploaded video, also known as a

“query work,” to a database of reference works. Id. There

1 We cite the ’988 patent as representative of the as-

serted patents’ specifications.

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4 NETWORK-1 TECHNOLOGIES, INC. v. GOOGLE LLC

are two versions of Google’s Content ID system at issue in

this appeal: an older version known as “LSH,” and a newer

version known as “Siberia.” Id.

The LSH version of Content ID works by searching

over an index of local sensitive hashing (“LSH”) bands, into

which “subfingerprints” corresponding to short snippets of

reference works are organized. Id. Subfingerprints for

query works and reference works are generated in the

same manner so that when a search is conducted for a

particular query work, the LSH version of Content ID

returns only the reference works associated with a

matching LSH band. Id. These reference works are then

further processed to eliminate candidates unlikely to be a

match with the query work. Id.

The Siberia version of Content ID works by generating

a sequence of embeddings corresponding to short snippets

or frames of content. Id. The reference embeddings are

further processed and stored in multiple reference indices

for searching, organized by content type. Id. at *5–6. Each

index is divided into smaller indices known as “shards”

that can each fit on one computer. Id. at *6.

II

In April 2014, Network-1 sued Google for infringement

of several claims of the asserted patents. 2 Decision,

2024 WL 1814296 at *7.

In June 2015, Google petitioned the United States

Patent and Trademark Office Patent Trial and Appeal

Board (“the Board”) for inter partes review (“IPR”),

2 The original complaint asserted only the ’988 and

’237 patents. Decision, 2024 WL 1814296 at *7. Later in

2014, Network-1 asserted the ’464 patent in a related case,

which was consolidated with the original one. See 14-cv-

02396-PGG-sn, ECF 137–38.

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NETWORK-1 TECHNOLOGIES, INC. v. GOOGLE LLC 5

asserting that the ’237 and ’988 patents were unpatentable

as anticipated and obvious. See id. The district court

stayed the case pending resolution of the IPRs. Id. The

Board instituted the IPRs, and the proceedings before the

Board turned on the term “non-exhaustive search.” Id.

The Board found that Google had failed to carry its burden

of demonstrating the claims were not patentable. Google

LLC v. Network-1 Techs., Inc., 726 F. App’x 779, 780

(Fed. Cir. 2018) (“IPR Appeal Decision”). Google appealed,

and we vacated and remanded the Board’s decision because

it erred in its construction of “non-exhaustive search.” Id.

at 787. Using the broadest reasonable construction

standard, we construed “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.” Id. at 786.

In January 2019, the Board terminated the

proceedings on remand upon joint stipulation of the

parties. Google, Inc. v. Network-1 Techs., Inc.,

No. IPR2015-00343, 2019 WL 104044 (P.T.A.B. Jan. 4,

2019). Following the Board’s decision, the district court

lifted the stay in this case and the parties narrowed the

claims to claim 17 of the ’988 patent; claims 1, 8, 10, 16, 18,

25, 27, and 33 of the ’464 patent; and claims 33–35 of the

’237 patent. See Decision, 2024 WL 1814296 at *9, 11.

In April 2024, the district court published a combined

claim construction and summary judgment order disposing

of all asserted claims. Id. at *38. It concluded that the

term “non-exhaustive search” recited in the asserted

claims of the ’988 and ’464 patents was indefinite,

rendering those claims invalid. Id. at *20. The district

court also granted summary judgment of noninfringement

of the asserted claims of the ’237 patent, concluding that

there was no genuine issue of material fact that Google’s

LSH and Siberia Content ID systems met the “sublinear

search” limitation. Id. at *34, 38.

Case: 24-1893 Document: 69 Page: 6 Filed: 04/23/2026

6 NETWORK-1 TECHNOLOGIES, INC. v. GOOGLE LLC

Network-1 timely appealed, and we have jurisdiction

under 28 U.S.C. § 1295(a)(1).

DISCUSSION

Network-1 appeals the district court’s invalidity and

summary judgment determinations. See Open. Br. 26–27.

We address each in turn.

I

Patent claims must “particularly point[] out and

distinctly claim[] the subject matter” regarded as the

invention. 35 U.S.C. § 112 ¶ 2. “A claim fails to satisfy this

statutory requirement and is thus valid for indefiniteness

if its language, read in light of the specification and

prosecution history, ‘fail[s] to inform, with reasonable

certainty, those skilled in the art about the scope of the

invention.’” Interval Licensing LLC v. AOL, Inc., 766 F.3d

1364, 1369–70 (Fed. Cir. 2014) (quoting Nautilus, Inc. v.

Biosig Instrs., Inc., 572 U.S. 898, 901 (2014)). Definiteness

is measured from the viewpoint of a skilled artisan “at the

time the patent was filed.” Nautilus, 572 U.S. at 908.

We review a determination of indefiniteness de novo.

Interval Licensing, 766 F.3d at 1370. Because “[g]eneral

principles of claim construction apply to indefiniteness,”

“we review a district court’s determinations of subsidiary

facts based upon extrinsic evidence for clear error, and

those based upon intrinsic evidence (the patent claims,

specification, and prosecution history) de novo.” HZNP

Medicines LLC v. Actavis Lab’ys UT, Inc., 940 F.3d 680,

688 (Fed. Cir. 2019) (citing Biosig Instrs., Inc. v. Nautilus,

Inc., 783 F.3d 1374, 1377–78 (Fed. Cir. 2015)).

The claims of the ’988 patent, which are representative

of the asserted claims of both that patent and the ’464

patent for purposes of analyzing the indefiniteness inquiry,

see Open. Br. 25, read as follows:

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NETWORK-1 TECHNOLOGIES, INC. v. GOOGLE LLC 7

15. A method for associating an electronic work

with an action, the electronic work comprising at

least one of audio and video, the method

comprising:

a) electronically extracting features from

the electronic work;

b) electronically determining an

identification of the electronic work based

on the extracted features, wherein the

identification is based on a non-exhaustive

search identifying a neighbor;

c) electronically determining an action

based on the identification of the electronic

work; and

d) electronically performing the action.

17. The method of claim 15, wherein the non-

exhaustive search is sublinear.

’988 patent col. 25 l. 65–col. 26 l. 9; id. col. 26 ll. 14–15

(emphases added).

Network-1 submits the following construction for “non-

exhaustive search” in contending that the term is not

indefinite: “a search designed to locate a [near] neighbor

without comparing to all possible matches (i.e., all records

in the reference data set), even if the search does not locate

a [near] neighbor.” Open. Br. 52. Google submits that the

district court was correct and the term is indefinite. Resp.

Br. 21. We conclude that the district court correctly

determined that the “non-exhaustive” search limitation is

indefinite.

We begin with the claim language. Claims 15 and 17,

taken together, refer to a “non-exhaustive search

identifying a neighbor” which can be “sublinear.” ’988

patent col. 26 ll. 5–6, 14–15. Other than demonstrating

that “non-exhaustive searches” do not inherently identify a

Case: 24-1893 Document: 69 Page: 8 Filed: 04/23/2026

8 NETWORK-1 TECHNOLOGIES, INC. v. GOOGLE LLC

neighbor (i.e., a close match) or are sublinear, the scope of

that language sheds little light on how a skilled artisan

would understand this term.

The written description also does not inform a skilled

artisan as to the scope of “non-exhaustive search” with

reasonable certainty. Our previous analysis of the term

from the IPR Appeal Decision, although not binding, is

informative. See 726 Fed. App’x at 786. There, Network-1

argued that the written description of a materially similar

patent reasonably conveyed the scope of the term because

it differentiated between “exhaustive searches” and “non-

exhaustive searches” because it “identifie[d] ‘a linear

search of all N entries’ as an ‘exhaustive search’” and

“[o]ther forms of matching,” such as “those based on

clustering, kd-trees, vantage point trees and excluded

middle vantage point forest,” as “non-exhaustive searches.”

Id. at 784–85. We rejected that argument because the

written description 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.” Id. at 785 (emphasis added).

That same reasoning applies here. Network-1 argues

that column 9, lines 24–32 of the written description

informs a skilled artisan as to the scope of “non-exhaustive

searches” with reasonable certainty. Open. Br. 52–53. But

that language fails to do so. The written description does

not contain the terms “exhaustive” or “non-exhaustive,” but

instead contrasts “linear search[es]” which “can be

computationally very expensive” with “[o]ther forms of

matching,” including “kd-trees, vantage point trees and

excluded middle vantage point forests.” ’988 patent col. 9

ll. 24–30. Although the written description refers to a

“linear search,” nothing in the written description suggests

that a skilled artisan would understand a “linear search”

to be interchangeable with a “non-exhaustive search.” Nor

does it inform a skilled artisan with reasonable certainty

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NETWORK-1 TECHNOLOGIES, INC. v. GOOGLE LLC 9

as to how much data within a record the “non-exhaustive

search” must consider.

Indeed, the phrase “non-exhaustive search” appears

nowhere in the original patent application that led to the

’988 and ’464 patents, but rather was added to the claims

nine years after the filing of the provisional application and

three years after the patent filing date which contained the

“linear search” language, in part to overcome prior art. J.A.

3245–53; see J.A. 79. To narrow “non-exhaustive search”

based on the “linear search” language used in the written

description would thus be to “view[] matters post hoc”––a

practice the Supreme Court has admonished. See

Nautilus, 572 U.S. at 911–12 (“[T]he definiteness inquiry

trains on the understanding of a skilled artisan at the time

of the patent application.”). It does the patent system or

the public no favor for this court to accept the

distinguishing of prior art with vague language that only

results in the uncertainty illustrated by this appeal and

this case’s long history.

Furthermore, the publications incorporated by

reference into the written description do not meaningfully

narrow the scope of “non-exhaustive search.” See ’988

patent col. 7 ll. 37–43, col. 9 ll. 32–38. The works cited––

Duda & Hart, 3 Fukunaga, 4 and the Yianilos papers 5––

either make passing references to an “exhaustive search”

3 Richard O. Duda & Peter E. Hart, Pattern Classifi-

cation and Scene Analysis, Stanford Research Institute

(1973), J.A. 2830–31, 2871–72.

4 Keinosuke Fukunaga, Introduction to Statistical

Pattern Recognition (2d), J.A. 2912, 2961.

5 Peter N. Yianilos, Excluded Middle Vantage Point

Forests for Nearest Neighbor Search, NEC Research Insti-

tute (Aug. 1, 1999), J.A. 1400–11; Peter N. Yianilos, Locally

Lifting the Curse of Dimensionality for Nearest Neighbor

Search, NEC Research Institute, J.A. 1413–22.

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10 NETWORK-1 TECHNOLOGIES, INC. v. GOOGLE LLC

without any further information, see J.A. 2872 (Duda &

Hart), J.A. 2961 (Fukunaga), or conflict with Network-1’s

proposed “non-exhaustive searches,” see J.A. 1403–04

(Yianilos describing a vantage point forest search possibly

being “exhaustive”).

Even if the intrinsic record were not dispositive on its

own, the extrinsic evidence further supports a conclusion

of indefiniteness. The district court considered the

declaration of Dr. Michael Mitzenmacher, Network-1’s

expert witness, as well as several academic papers which

provided definitions of “exhaustive” versus “non-

exhaustive searches.” Decision, 2024 WL 1814296 at *15–

18; see J.A. 2764–95 (Mitzenmacher declaration). It

ultimately concluded that the extrinsic evidence did not

support Network-1’s construction but instead

“highlight[ed] the vague nature of ‘exhaustive search’ and

‘non-exhaustive search.’” Decision, 2024 WL 1814296 at

*18.

We find no clear error in the district court’s analysis.

Mitzenmacher’s declaration simply repeats the same failed

points above regarding the written description. See J.A.

2781–86. The declaration also relies on academic papers

Denny 6 and Orwant. 7 Id. at 2783, 2786–87. But these do

not inform a skilled artisan as to the meaning of “non-

exhaustive search.” Orwant states that “the definition of

exhaustive search is vague.” J.A. 3020. And Denny defines

a “non-exhaustive search strategy” as one that “traverse[s]

the search space more or less at random and thus certain

states may never be examined.” J.A. 3011. But as the

6 Paul C. Denny, Search and Enumeration Tech-

niques for Incidence Structures, Centre for Discrete Math-

ematics and Theoretical Computer Science (May 1998),

J.A. 3003, 3010–12.

7 Jon Orwant et al., Mastering Algorithms with Perl

(Aug. 1999), J.A. 3015, 3017–20.

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NETWORK-1 TECHNOLOGIES, INC. v. GOOGLE LLC 11

district court observed, this is inconsistent with Network-

1’s proposed construction because the proposed

construction does not have such a requirement to “traverse

the search space more or less at random.” Decision,

2024 WL 1814296 at *17.

Network-1’s argument to the contrary is unpersuasive.

It argues that our analysis of “non-exhaustive search” in

the IPR Appeal Decision should not inform our decision

here because it was under the broadest reasonable

interpretation (“BRI”) standard. Open. Br. 57–58. We

disagree. It is true that we utilized the BRI, not Phillips,

standard in the IPR Appeal Decision. See 726 Fed. App’x

at 786. But the analysis regarding the written

description’s lack of identification of “non-exhaustive

search” is the same––i.e., regardless of standard, the

written description does not draw a clear line between

“exhaustive” and “non-exhaustive.” See id. at 785.

In sum, neither the intrinsic nor extrinsic evidence

offers sufficient guidance to a skilled artisan as to the scope

of the term “non-exhaustive search” with reasonable

certainty. The asserted claims of the ’988 and ’464 patent

are thus invalid for indefiniteness.

II

We next consider the district court’s grant of summary

judgment of noninfringement of the ’237 patent. 8 “We

review the district court’s grant of summary judgment

under the law of the regional circuit in which the court sits,

here, the Second Circuit.” See Medgraph, Inc. v. Medtronic,

8 Although the written description of the ’237 patent

includes the same disputed language regarding “linear

search” versus “other forms of searching,” ’237 patent col.

8 ll. 59–67, the definiteness of the asserted claims of the

’237 patent is not before us. We accordingly do not deal

with it here.

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12 NETWORK-1 TECHNOLOGIES, INC. v. GOOGLE LLC

Inc., 843 F.3d 942, 947 (Fed. Cir. 2016) (citation omitted).

“The Second Circuit reviews a grant of summary judgment

without deference, construing the evidence in the light

most favorable to the nonmovant and drawing all

reasonable inferences in that party’s favor.” Id. (citing

Kuebel v. Black & Decker Inc., 643 F.3d 352, 358 (2d Cir.

2011)). “Summary judgment may only be granted when no

‘reasonable jury could return a verdict for the nonmoving

party.’” Id. (quoting Anderson v. Liberty Lobby, Inc.,

477 U.S. 242, 248 (1986)).

“Summary judgment of noninfringement is

appropriate where the patent owner’s proof is deficient in

meeting an essential part of the legal standard for

infringement, since such failure will render all other facts

immaterial.” Telemac Cellular Corp. v. Topp Telecom, Inc.,

247 F.3d 1316, 1323 (Fed. Cir. 2001). “[I]n order for a court

to find infringement, the plaintiff must show the presence

of every . . . [limitation] or its substantial equivalent in the

accused device.” Wolverine World Wide, Inc. v. Nike, Inc.,

38 F.3d 1192, 1199 (Fed. Cir. 1994).

Claim 33 of the ’237 patent, which is representative for

purposes of analyzing summary judgment, reads as

follows:

33. A computer-implemented method comprising:

a) obtaining, by a computer system includ-

ing at least one computer, media work ex-

tracted features that were extracted from a

media work, the media work uploaded from

a client device;

b) determining, by the computer system,

an identification of the media work using

the media work extracted features to per-

form a sublinear approximate nearest

neighbor search of reference extracted

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NETWORK-1 TECHNOLOGIES, INC. v. GOOGLE LLC 13

features of reference identified media

works; and

c) determining, by the computer system, an

action based on the determined identifica-

tion of the media work.

’237 patent col. 28 ll. 5–16 (emphasis added).

The parties’ dispute centers on whether the LSH or

Siberia versions of Content ID meet the “sublinear search”

limitation as recited in claim 33 of the ’237 patent. Open.

Br. 30; Resp. Br. 41. The parties agree that LSH or Siberia

meet the “sublinear” limitation if its “execution time scales

with a less than linear relationship to the size of the data

set to be searched, assuming computing power is held

constant.” Open. Br. 44; Resp. Br. 41; see also Decision,

2024 WL 18142962024, at *28. The district court

concluded that Network-1 did not create a material issue

of fact as to whether either version met this limitation and

thus granted summary judgment of noninfringement. Id.

at *34, *38. We address each version in turn.

A

We begin with the LSH version of Content ID.

Network-1 relied on three pieces of evidence in opposing

summary judgment before the district court: (1) the

academic work of Google research scientist Dr. Shumeet

Baluja (“the Baluja papers”) and his testimony; (2) a

Google 2010 draft document; and (3) Mitzenmacher’s

report. See Decision, 2024 WL 18114296 at *28. The

district court concluded that none of the three created a

genuine issue of material fact as to whether the LSH

version was sublinear. Id. at *34. After de novo review of

each, we agree with the district court.

The Baluja papers and his testimony do not create a

genuine issue of material fact. See J.A. 9690–9703 (paper

titled “Waveprint”); J.A. 9714–51 (paper titled “Learning

to Hash”); J.A. 7225–26, 7321–24, 7361–63, 7371–74,

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14 NETWORK-1 TECHNOLOGIES, INC. v. GOOGLE LLC

7398–7400, 7403, 7406 (Baluja testimony). Network-1

argues that the papers contain statements which a

reasonable trier of fact could interpret to describe LSH

systems as sublinear. See Open. Br. 32–33. But neither

paper describes the LSH version of Content ID. See

generally J.A. 9690–703; J.A. 9714–51. Rather, they

describe a system called Waveprint, which uses computer-

vision techniques for identifying audio, see J.A. 9690, and

describe hash functions only generally without addressing

the LSH version, see J.A. 9716–18. And at his deposition,

Baluja confirmed that he was not involved in

implementation, but rather only research. J.A. 7399.

Network-1’s argument is thus unavailing, as there is

insufficient evidence connecting Baluja’s papers or

testimony to Google’s LSH version to create a genuine issue

of material fact.

The Google 2010 draft document suffers from a similar

flaw: there is insufficient evidence connecting it to the

implementation of the LSH version. Network-1 argues it

creates a genuine issue of material fact because it describes

Google’s matching infrastructure as having LSH tables

that will scale sublinearly. Open. Br. 34–35 (citing J.A.

9387). We disagree. There is no evidence in the record that

Google implemented such tables from the 2010 draft

document. Indeed, the document contemplates two types

of LSH tables: one that scales sublinearly and one that does

not. J.A. 9387. But Network-1 points to no evidence that

one was implemented over the other. See Open. Br. 34–36.

Rather, Network-1 is essentially arguing that Google was

capable of infringing the ’237 patent. But even with all

reasonable inferences in Network-1’s favor, there is no

evidence of what Google actually implemented to present a

genuine issue of material fact. See Miken Composites,

L.L.C. v. Wilson Sporting Goods Co., 515 F.3d 1331, 1340–

41 (Fed. Cir. 2008) (affirming summary judgment of

noninfringement when there was no record evidence of

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NETWORK-1 TECHNOLOGIES, INC. v. GOOGLE LLC 15

literal infringement, even though the possibility of

infringement existed).

Finally, the Mitzenmacher report does not create a

genuine issue of material fact. Indeed, it relies

significantly on the Baluja papers, Baluja’s testimony, and

the Google 2010 draft document. See J.A. 6598–99. But as

we explained above, those do not create a genuine issue of

material fact because there is insufficient evidence

connecting them to the implementation of the LSH version.

Furthermore, Mitzenmacher’s review of Google’s code does

not demonstrate that the LSH version is sublinear; it

rather steps through the process of the content

identification without any analysis as to how it is

sublinear. See J.A. 6599–6602. Because Mitzenmacher’s

report contains no other support, it does not create a

genuine issue of material fact. See Minkin v. Gibbons, P.C.,

680 F.3d 1341, 1352 n.5 (Fed. Cir. 2012) (“It is well-

established that unsupported expert opinions do not create

a genuine issue of material fact.” (citations omitted)).

In sum, no piece of evidence considered by the district

court, and which Network-1 relies on before us, creates a

genuine issue of material fact. Google is thus entitled to

judgment as a matter of law of noninfringement of the ’237

patent as to the LSH version.

B

We next consider the Siberia version. The district

court granted summary judgment of noninfringement

because, in its view, the evidence indicated that the Siberia

version did not scale sublinearly. See Decision, 2024 WL

1814296 at *36.

Upon de novo review, we conclude that there is a

genuine issue of material fact regarding the Siberia version

so as to preclude summary judgment of noninfringement of

the ’237 patent.

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16 NETWORK-1 TECHNOLOGIES, INC. v. GOOGLE LLC

First, there is a fundamental dispute as to how the

Siberia version functions. Network-1 argues that the

Siberia version is sublinear because the algorithm has

different “tunable knobs,” which Google adjusted to lower

resource costs. See Open. Br. 45–47 (citing J.A. 9812; J.A.

10395–96). Google counters that the Siberia version is

undisputedly linear because it “search[es] a fixed fraction

of the data set.” Resp. Br. 54 (citing J.A. 3953). And it

further argues that “[e]ven if Google reduced the number

of searched [components], Siberia would still search a

predetermined proportion of all partitions and thus scale

linearly.” Id. at 60 (citing J.A. 4447–48).

We conclude that this dispute is best left to a factfinder.

With all reasonable inferences in Network-1’s favor, a

factfinder could find that the Siberia version as an overall

system was designed to have an execution time which

scaled in less than a proportional relationship to the size of

the reference set because the “tunable knobs” allowed the

system to adapt to a growing dataset size. See J.A. 9812;

J.A. 10335; J.A. 10378–79; J.A. 10395–96. For purposes of

summary judgment, it is immaterial that the Siberia

version, once that “knob” is turned, may search that new

“fixed fraction” linearly.

Furthermore, an internal Google document regarding

the Siberia version states that Google “will need . . . a

sublinear search.” J.A. 10265 (emphasis added). That is

also enough to create a factual issue; with reasonable

inferences in Network-1’s favor, a factfinder could consider

this document to describe the implementation of the

Siberia version as sublinear. Google argues this document

“is referring to a potential strategy, not Siberia as

implemented.” Resp. Br. 56. That argument is

unpersuasive. A factfinder could reasonably read the

phrase “will need” as imposing a requirement of a

sublinear search on any future Siberia implementation.

J.A. 10265. It thus creates a genuine issue of material fact

regarding whether the Siberia version is sublinear.

Case: 24-1893 Document: 69 Page: 17 Filed: 04/23/2026

NETWORK-1 TECHNOLOGIES, INC. v. GOOGLE LLC 17

Because there is a genuine issue of material fact,

summary judgment of noninfringement of the ’237 patent

as to the Siberia version is inappropriate.

CONCLUSION

We have considered the remainder of the parties’

arguments but find them unpersuasive. We reverse the

district court’s grant of summary judgment of

noninfringement of the ’237 patent as to the Siberia version

of Content ID and remand for further proceedings. We

affirm the district court’s conclusion of indefiniteness as to

the ’988 patent and ’464 patent. We affirm the district

court’s grant of summary judgment of noninfringement of

the ’237 patent as to the LSH version of Content ID.

AFFIRMED IN PART, REVERSED IN PART, AND

REMANDED

COSTS

No costs.