NOTE: This disposition is nonprecedential.

 

United States Court of Appeals 

for the Federal Circuit ______________________ 

UNILOC 2017 LLC.,

Appellant

v.

NETFLIX, INC.,

Appellee

______________________ 

2021-2085

______________________ 

Appeal from the United States Patent and Trademark 

Office, Patent Trial and Appeal Board in No. IPR2020-

00044.

______________________ 

Decided: December 15, 2022

______________________ 

NATHAN K. CUMMINGS, Etheridge Law Group, Southlake, TX, argued for appellant. Also represented by JAMES 

ETHERIDGE, RYAN S. LOVELESS. 

 PATRICK JOHN MCKEEVER, Perkins Coie LLP, San Diego, CA, argued for appellee. Also represented by 

MATTHEW COOK BERNSTEIN; DAN L. BAGATELL, Hanover, 

NH; TARA LAUREN KURTIS, Chicago, IL. 

 ______________________ 

Before DYK, TARANTO, and HUGHES, Circuit Judges.

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2 UNILOC 2017 LLC. v. NETFLIX, INC. 

HUGHES, Circuit Judge. 

Uniloc 2017 LLC appeals a decision by the Patent Trial 

and Appeal Board that claims 1, 3, 5, and 6 of U.S. Patent 

No. 6,584,229 are unpatentable. Because we reject Uniloc’s 

arguments that the Board improperly construed two claim 

limitations, we affirm. 

I 

A 

U.S. Patent No. 6,584,229 relates to a method for encoding videos. A video is a sequence of moving images, or 

“frames.” ’229 patent at 1:27–31; see also Netflix, Inc. v. 

Uniloc 2017 LLC, IPR No. 2020–00044, Ex. 1002, Declaration of Eli Saber, Ph.D. in Support of Petition (Saber Decl.) 

¶ 30. Frames are commonly defined by unit of “macroblock.” ’229 patent at 1:27–31; Saber Decl. ¶ 32. A macroblock is a two-dimensional square containing a set 

number of brightness, color hue, and color saturation values. Saber Decl. ¶ 32. A typical macroblock is 16 brightness 

values wide by 16 brightness values long, with a corresponding number of color hue and saturation values dispersed throughout the square. Id. A “pixel” is the unit used 

to describe each brightness value. To put it simply: a macroblock is a 16x16 block of pixels, and a frame is a grid of 

macroblocks. Id. at ¶¶ 31–33.

Encoding a video requires translating the pictures in 

each frame into a compressed code that can be efficiently 

stored or transmitted. ’229 patent at 1:17–37. Before the 

priority date of the ’229 patent, conventional techniques 

were commonly used to separate each frame into a foreground object region and a background region. Id. at 1:21–

25. It was also well-known that working at the macroblocklevel is more efficient than individually coding each of the 

256 pixels that make up the macroblock. Id. at 1:51–63. 

The ’229 patent purports to claim a more efficient encoding method by only coding at the pixel-level when 

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necessary and, where possible, reusing code for macroblocks in the background area. Id. at 1:66–2:8. The specification asserts that dividing a video by pixel using “the 

conventional region division technique” is “very complicated,” and it is hard to use conventional processes “in real 

time.” Id. at 1:51–54. The patent adds that coding and 

transmitting by pixel is inefficient. Id. at 1:54–63. It purports to solve these problems by dividing the frame into two 

macroblock-based regions. Id. at 1:66–2:21. One region is a 

stationary background region, which contains the portion 

of the image that remains the same from one frame in the 

sequence to the next. Id. The other is the moving object region, which contains the portion of the image that changes

from the previous frame. Id. New pixel-level coding is only 

necessary for the moving object region, and so the code for 

the background region can be reused at the macroblocklevel to avoid redundancy. Id. Claim 1 is representative: 

1. A method, for use in an [sic] macroblock-based 

object oriented coding of a [sic] image signal, 

wherein the image signal has a stationary background region and an object region and contains a 

current frame and a previous frame, each frame including a plurality of macroblocks, comprising the 

steps of:

a) dividing the stationary background region and 

the object region from an inputted video in a macroblock-by-macroblock basis by using a difference 

between the previous frame and the current frame;

b) coding shape information of the object region by 

using a known coding technique to generate coded 

shape information;

c) coding pixel information of each macroblock contained in the object region by using a selected 

known coding technique to generate coded object 

pixel information;

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4 UNILOC 2017 LLC. v. NETFLIX, INC. 

d) generating coded pixel information of a previous 

frame macroblock corresponding to each current 

frame macroblock contained in the stationary background region as coded stationary pixel information; and

e) storing or transmitting coded data coded shape 

information, coded object pixel information and 

coded stationary pixel information as coded image 

signal, and

wherein the step d) includes the step of reusing corresponding coded pixel information macroblock 

contained in the previous frame without coding the 

pixel information of each macroblock contained in 

the current frame when a difference between a 

pixel value of the macroblock of the current frame 

and that of the macroblock of the previous frame in 

the same position is identical to or smaller than a 

predetermined threshold value.

’229 patent at 3:42–4:21. 

B 

Appellee, Netflix, Inc., petitioned for inter partes review of independent claim 1 and dependent claims 3, 5, and 

6 of the ’229 patent under two obviousness grounds. The 

primary art reference in the first ground discloses a 

method for segmenting a frame into macroblock-based object and background regions. Raj Talluri, et al., A Robust, 

Scalable, Object-Based Video Compression Technique for 

Very Low Bit-Rate Coding, 7 IEEE TRANSACTIONS ON 

CIRCUITS AND SYS. FOR VIDEO TECH. 1 (Feb. 1997) (Talluri). 

Talluri discloses two parts of the segmentation step: (1) 

comparing the current frame with the previous frame to 

identify the moving objects, and (2) bounding each moving 

object region and background region with rectangles and 

tiling the rectangles with macroblocks. Talluri at 224. The

resulting regions are macroblock-based after step two, but 

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Talluri does not require comparing at the macroblock-level 

during the first step. 

The Board found all challenged claims unpatentable 

under the first ground and did not reach the second ground. 

J.A. at 37–38. Uniloc appeals, arguing the Board erred in 

its claim construction of the “dividing” limitation and the 

“selected known coding technique” limitation. We have jurisdiction under 28 U.S.C. § 1295(a)(4)(A).

II

Claim construction is a question of law that depends on 

underlying findings of fact. Teva Pharms. USA, Inc. v. 

Sandoz, Inc., 574 U.S. 318, 325–28 (2015). We review the 

Board’s constructions de novo and its factual findings for 

substantial evidence. Immunex Corp. v. Sanofi-Aventis US 

LLC, 977 F.3d 1212, 1217–18 (Fed. Cir. 2020).

III

A 

We begin with the “dividing” limitation of claim 1: 

dividing the stationary background region and the 

object region from an inputted video in a macroblock-by-macroblock basis by using a difference 

between the previous frame and the current frame

. . . 

’229 patent at 3:48–51 (emphasis added). The dispute is 

whether “macroblock-by-macroblock basis” requires the act

of dividing to be done macroblock-by-macroblock (i.e., one 

macroblock at a time); or whether it simply requires that 

the dividing results in separate macroblock-based regions. 

The Board held the latter: the limitation requires only (1) 

using a difference between the previous frame and the current frame to (2) result in macroblock-based object and 

background regions. J.A. 10–11. We agree. 

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When construing a claim limitation, we rely first on intrinsic evidence and then on extrinsic evidence if necessary. Phillips v. AWH Corp., 415 F.3d 1303, 1317 (Fed. Cir. 

2005) (en banc). When the technology is complicated and 

the intrinsic record is unclear, expert testimony and other 

extrinsic evidence may be decisive. See Wyers v. Master 

Lock Co., 616 F.3d 1231, 1240 n.5 (Fed. Cir. 2010) (noting 

that expert testimony is “sometimes essential,” especially 

“in cases involving complex technology.”). Such is the case 

here. 

The relevant intrinsic evidence before us is: (1) the 

claim language itself, (2) portions of the specification that 

describe the dividing step, and (3) portions of the specification that explain the purpose of the claimed invention and 

how it purportedly solves problems in the prior art.1 After 

considering all the evidence de novo, we conclude that the 

intrinsic record is ambiguous as to the meaning of “macroblock-by-macroblock basis.” 

First, the claim language itself is unclear because it 

could be read to support either construction equally. On 

one hand, we can imagine how a reader might interpret 

1 Netflix asks us to ignore Uniloc’s arguments as related to the third category of intrinsic evidence, claiming

that such arguments were forfeited. Oral Argument at 

12:06. But our forfeiture doctrine does not “preclude a 

party from proffering additional or new supporting arguments, based on evidence of record, for its claim construction.” Interactive Gift Exp., Inv. v. Compuserve Inc., 256 

F.3d 1323, 1347 (Fed. Cir. 2001). Here, Uniloc merely cited 

additional support in the specification to support the same 

argument it had always made—“macroblock-by-macroblock basis,” includes how the dividing occurs, not just

what results from that division. We do not consider Uniloc’s 

arguments related to this evidence to be forfeited, and thus 

we consider all cited portions of the record.

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“macroblock-by-macroblock” to imply comparisons using 

“one macroblock-by-one macroblock.” But on the other 

hand, the structure of the claim can be read to set forth 

only two requirements: a “what” (dividing the stationary

background region and the object region from an inputted 

video in a macroblock-by-macroblock basis) and a “how” (by 

using a difference between the previous frame and the current frame). Given these competing reasonable interpretations, it is not clear based on the claim language what is 

meant by “macroblock-by-macroblock basis.”2 

Uniloc disagrees, arguing that the claim language unambiguously requires the dividing step to occur one macroblock at a time. But this asks us to read language into 

the claim that is simply not there. The claim language is 

not comparing using “one macroblock at a time,” nor is it 

comparing “one macroblock-by-one macroblock.” If anything, the fact that the language does not require comparing at the macroblock-level—but instead explicitly requires

comparing between frames—suggests that a person of ordinary skill in the art would not read Uniloc’s requirement 

into the claim language. ’229 patent at 3:50–51 (requiring 

that the division occurs by “using a difference between the 

previous frame and the current frame . . .”) (emphasis 

added). 

Uniloc also argues that the preamble clarifies the 

meaning of “macroblock-by-macroblock basis.” The preamble states: “wherein the image signal has a stationary background region and an object region and contains a current 

frame and a previous frame, each frame including a plurality of macroblocks.” ’229 at 3:42–47 (emphasis added). 

2 Moreover, while we treat “in a macroblock-by-macroblock basis” as a typographical error, preferring the 

phrase “on a macroblock-by-macroblock basis,” this claim 

drafting mistake makes already ambiguous claim language 

even less clear.

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8 UNILOC 2017 LLC. v. NETFLIX, INC. 

While the preamble may give context to the meaning of a 

limitation, it does not make the phrase “macroblock-bymacroblock basis” any clearer. As the Board acknowledged, 

the “previous frame” and “current frame” in the preamble 

are the same terms used in the dividing limitation. J.A. 10. 

The preamble describes both the current and previous 

frames as including “a plurality of macroblocks.” Uniloc argues this means the first frame must already be defined at 

the macroblock level. J.A. 11. But every frame is technically defined at the macroblock level. The macroblocks exist as a unit of measuring the frame, no matter if we have 

drawn invisible dividing lines around them or not. The 

Board’s construction is consistent with the preamble language. That the previous frame can be expressed in units 

of macroblocks does not require the dividing to be done one 

macroblock at a time. Thus, neither the claim language nor 

the preamble dictates Uniloc’s narrow interpretation of the 

dividing step. 

Likewise, the specification also does not clarify what is 

meant by “macroblock-by-macroblock basis.” It is worth 

noting that nowhere in the specification is this term defined. In fact, the phrase “macroblock-by-macroblock basis” 

is only ever used once in the entire patent, and that is in 

claim 1. 

Moreover, the portions of the specification that describe the dividing step more generally are still unclear. 

The paragraph of the specification cited by Board as describing the dividing step begins: 

The video signal is divided into a macroblock-based

stationary back ground [sic] region and a macroblock-based moving object region by using the 

difference between a previous frame of the input 

video signal and a current frame of the input video 

at step 10. 

JA 10–11 (citing ’229 patent at 2:45–49). This language 

suggests that the difference between a previous frame and 

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a current frame need not be determined one macroblock at 

a time, so long as the video signal is ultimately “divided 

into a macroblock-based stationary back ground [sic] and a 

macroblock-based moving object region . . .,” as the specification describes. 

Uniloc points out that the rest of that paragraph provides an example by which the dividing step occurs one 

macroblock at a time. Opening Br. at 14 (citing ’229 patent 

at 2:53–60). But we do not limit the claim language to examples used in the specification. E.g., Williamson v. Citrix 

Online, LLC, 792 F.3d 1339, 1346–47 (Fed. Cir. 2015) 

(“This court has repeatedly ‘cautioned against limiting the 

claimed invention to preferred embodiments or specific examples in the specification.’”) (quoting Teleflex, Inc. v. Ficosa N. Am. Corp., 229 F.3d 1313, 1328 (Fed. Cir. 2002)). 

The patent describes this example as one of multiple “wellknown techniques,” suggesting there are other methods 

that would fall within the dividing limitation. This paragraph does not dictate dividing one macroblock at a time. 

Nor do the portions of the specification about the purpose of the invention and avoiding problems in the prior art 

clarify the meaning of “macroblock-by-macroblock basis.” 

The specification alludes to at least two purposes of dividing the object region and background region into macroblocks: (1) to make coding more efficient, Responsive Br.

at 16–17 (citing ’229 patent at 1:54–62; 2:4–6; 3:10–19); 

and (2) to avoid dividing at the pixel-level, Reply Br. at 4–

5, 16–17 (citing ’229 patent at 1:38–41; 2:2–6). The specification then goes on to describe how those purposes are 

achieved, starting with the first step: “wherein the inputted video is to be divided into an [sic] background region 

and a foreground object region by unit of macroblock,” ’229 

patent at 2:9–12 (emphasis added). These statements, none 

of which use the term “macroblock-by-macroblock basis,” 

do not dispositively clarify the meaning of this language. 

They can be read to support either interpretation of the 

claim language. 

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Thus, after considering the relevant portions of the intrinsic record as a whole, we are left with no clear answer 

as to whether a person of ordinary skill in the art would 

understand the “dividing” limitation to require dividing 

one macroblock at a time. This leaves us to consider the 

extrinsic record. Helmsderfer v. Bobrick Washroom Equip., 

Inc., 527 F.3d 1379, 1382 (Fed. Cir. 2008) (affirming the 

trial court’s reliance on extrinsic evidence where the intrinsic record was not sufficiently clear to determine the plain 

meaning of a claim limitation). The only extrinsic evidence 

provided by Uniloc is a dictionary definition of “basis,” 

which defines the word as “the system or principles according to which an activity or process is carried on.” Reply Br.

at 6. We do not find this lone dictionary definition helpful 

in clarifying Uniloc’s interpretation. 

More helpful is the expert testimony of Dr. Eli Saber, 

Netflix’s expert. “Where the Board looks beyond the intrinsic evidence and consults extrinsic evidence, we review the 

Board’s subsidiary factual findings concerning such extrinsic evidence for substantial evidence.” Arista Networks, 

Inc. v. Cisco Sys., Inc., 908 F.3d 792, 796 (Fed. Cir. 2018). 

The substantial evidence standard is satisfied “if a reasonable mind might accept the evidence as adequate to support the finding.” Almirall, LLC v. Amneal Pharms. LLC, 

28 F.4th 265, 271–72 (Fed. Cir. 2022). 

Here, we hold that substantial evidence supports the 

Board’s findings concerning Dr. Saber’s testimony. The 

Board credited Dr. Saber’s testimony on claim construction, citing to his statement about how a person of ordinary 

skill (himself) would interpret the term “macroblock-bymacroblock basis.” J.A. 8 (citing J.A. 1355–56). A reasonable mind could have accepted Dr. Saber’s testimony as adequate to support the finding that a person of skill in the 

art would not have read “macroblock-by-macroblock basis” 

to require dividing one macroblock at a time. In particular, 

Dr. Saber filed two declarations during the proceeding, one 

with the petition and one with the reply. Dr. Saber’s first 

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declaration set forth ample evidence that he qualifies as a

person of ordinary skill in the art and that he reviewed the 

claim language and specification through that lens. Saber 

Decl. ¶¶ 5–22. His declarations also explained the technology and how a person of ordinary skill in the art would understand that technology, ultimately leading to his claim 

language analysis cited by the Board. 

Uniloc, in contrast, offered no expert evidence, whether 

to explain technological facts or usage in the field that 

might help clarify the meaning or implications of the specification or for any other purpose. In its reply brief on appeal, Uniloc suggests it would defeat the purpose of the 

invention to compare the brightness between frames pixelby-pixel due to the bandwidth required to do so. But there 

is no evidence in the record that a pixel-by-pixel comparison of brightness would in fact use excessive bandwidth 

and frustrate the goal of the invention. Also important is 

that Netflix’s expert’s, Dr. Saber’s, opinions are consistent

with the intrinsic record. As discussed above, the meaning 

of “macroblock-by-macroblock basis” is left ambiguous after a careful review of the intrinsic evidence. This is not a 

case where the Board has credited extrinsic evidence that 

runs afoul of the claim language or the specification. To the 

contrary, the Board cited the specification as additional 

support for Dr. Saber’s testimony and the Board’s finding 

that “macroblock-by-macroblock basis” did not require dividing one macroblock at a time. J.A. 8–9. Thus, the Board 

properly relied on Dr. Saber’s testimony to confirm that all 

that is required to meet this limitation is (1) using a difference between the previous frame and the current frame to 

(2) result in macroblock-based object and background regions.

We have considered the parties’ remaining arguments 

and find them unpersuasive. We affirm as to the “dividing” 

limitation. 

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12 UNILOC 2017 LLC. v. NETFLIX, INC. 

B 

Next, we address the “selected known coding technique” limitation: “coding pixel information of each macroblock contained in the object region by using a selected 

known coding technique to generate coded object pixel information . . . .” ’229 patent at 4:1–3 (emphasis added). 

Uniloc argues that the use of the word “selected” requires 

a construction that includes a separate step of selecting 

which “known coding technique” to use. Opening Br. at 17–

23. The Board rejected this argument, holding that the 

claimed method does not require an additional selecting 

step. 

We agree with the Board. Similar to our precedent in 

Summit 6, LLC v. Samsung Electronics Company, “selected” is “not a step in the claimed method,” but is a 

“phrase that characterizes the claimed” use of a known coding technique to code the pixel information of the object region. 802 F.3d 1283, 1290–92 (Fed. Cir. 2015). Thus, the 

Board did not err by not requiring a separate step of “selecting.” 

Uniloc contends that we must give meaning to all the 

words in the claim and that using a different term generally presumes a different meaning. But the fact that the 

preceding limitation uses the term “known coding technique” without using the word “selected” does not import a 

new “selecting” requirement into this limitation. It is not 

that the word “selected” carries no weight. The known coding technique must have been selected at some point—just 

not as part of the encoding method. 

Uniloc also points to step 20 of the specification as support for the “selecting” requirement. Opening Br. at 19. But 

step 20 relates to determining a coding technique for the 

shape coding of the object region (limitation 1(b)), not for 

pixel coding (limitation 1(c)). The parts of the figure that 

appear to relate to limitation 1(c), steps 40 and 50, say 

nothing about selecting a particular coding technique. 

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Steps 40 and 50 only show that one first determines 

whether to apply the known coding technique, and then 

uses the known coding technique if applicable. There is no 

reference in the specification to suggest “selected known 

coding technique” requires some unspecified selecting step. 

Nor has Appellant cited any prosecution history or extrinsic evidence to support this reading of the claim. Appellant 

seeks to turn the general presumption that different 

phrases have different meanings into a bright line rule that 

saves the patent from unpatentability. We have rejected 

such an inflexible rule before, and we continue to do so 

here. SimpleAir, Inc. v. Sony Ericsson Mobile Commc’ns 

AB, 820 F.3d 419, 429 (Fed. Cir. 2016). 

We have considered the parties’ remaining arguments 

and find them unpersuasive. We affirm as to the “selected 

known coding technique” limitation. 

AFFIRMED 

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