IN THE UNITED STATES DISTRICT COURT

FOR THE WESTERN DISTRICT OF TEXAS

WACO DIVISION

WSOU INVESTMENTS, LLC d/b/a 

BRAZOS LICENSING AND 

DEVELOPMENT,

Plaintiff,

v.

DELL TECHNOLOGIES INC., DELL

INC., AND EMC CORPORATION,

Defendants.

Case No. 6:20-cv-00477-ADA

Case No. 6:20-cv-00482-ADA

JURY TRIAL DEMANDED

DEFENDANTS’ RESPONSIVE CLAIM CONSTRUCTION BRIEF 

REGARDING PATENT NOS. 7,424,020 & 8,913,489 

Case 6:20-cv-00477-ADA Document 87 Filed 04/14/21 Page 1 of 11
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TABLE OF CONTENTS

Page

I. DISPUTED TERMS FROM THE ’020 PATENT............................................................. 1

A. “removing, at the network node, the protocol data of a portion of protocol 

layers from the received data stream” (claim 1) / “removes protocol data 

from a portion of protocol layers from a data stream” (claim 6)............................ 1

B. “a control unit which removes protocol data from a portion of protocol 

layers from a data stream received from the communication network via 

the second interface, the data stream comprising useful data and the 

protocol data, and switches a remaining data stream to be transmitted to 

one of the terminals via the first interface” (claim 6)............................................. 2

1. The term is indefinite under IPXL .............................................................. 2

2. Alternatively, the term is subject to 35 U.S.C. § 112, ¶ 6 .......................... 3

C. “bus system” (claims 1 and 6) ................................................................................ 3

II. DISPUTED TERM FROM THE ’489 PATENT ............................................................... 4

A. “the first set of port interfaces of the multi-chassis link aggregate” (claims 

1, 8, 15) ................................................................................................................... 4

Case 6:20-cv-00477-ADA Document 87 Filed 04/14/21 Page 2 of 11
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TABLE OF AUTHORITIES

Page(s)

Cases

3M Innovative Props. Co. v. Avery Dennison Corp.,

350 F.3d 1365 (Fed. Cir. 2003)..................................................................................................4

Baldwin v. New York,

2015 WL 6696505 (W.D.N.Y. Nov. 2, 2015) ...........................................................................4

Bushnell Hawthorne, LLC v. Cisco Systems, Inc.,

813 F. App’x 522 (Fed. Cir. May 14, 2020)..............................................................................4

California Inst. of Tech. v. Hughes Commc’ns Inc.,

35 F. Supp. 3d 1176 (C.D. Cal. 2014) .......................................................................................1

Canon, Inc. v. TCL Elecs. Holdings Ltd.,

2020 WL 2098197 (E.D. Tex. May 1, 2020).............................................................................3

InterDigital Commc’n, LLC v. Int’l Trade Comm’n,

690 F.3d 1318 (Fed. Cir. 2012)..................................................................................................1

K-2 Corp. v. Valomon S.A.,

191 F.3d 1356 (Fed. Cir. 1999)..................................................................................................5

MasterMine Software, Inc. v. Microsoft Corp.,

874 F.3d 1307 (Fed. Cir. 2017)..................................................................................................2

Mayes v. E.P.A.,

2008 WL 65178 (E.D. Tenn. Jan. 4, 2008)................................................................................4

Merck & Co. v. Teva Pharm. USA, Inc.,

395 F.3d 1364 (Fed. Cir. 2005)..................................................................................................5

Nautilus, Inc. v. Biosig Instruments, Inc.,

572 U.S. 898 (2014)...................................................................................................................1

Rembrandt Data Techs., LP v. AOL, LLC,

641 F.3d 1331 (Fed. Cir. 2011)..................................................................................................2

Spherix Inc. v. Matal,

703 F. App’x 982 (Fed. Cir. 2017) ............................................................................................5

Union Pac. Res. Co. v. Chesapeake Energy Corp.,

236 F.3d 684 (Fed. Cir. 2001)....................................................................................................1

Well-man, Inc. v. Eastman Chem. Co.,

642 F.3d 1355 (Fed. Cir. 2011)..................................................................................................5

Case 6:20-cv-00477-ADA Document 87 Filed 04/14/21 Page 3 of 11
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TABLE OF ABBREVIATIONS

Abbreviation Term/Document(s)

’020 patent U.S. Patent No. 7,424,020

’489 patent U.S. Patent No. 8,913,489

DefBr. Responsive Claim Construction Brief (Case No. 6:20-cv-00477-

ADA, Dkt. 83; Case No. 6:20-cv-00482-ADA, Dkt. 79)

Defendants Dell Technologies Inc., Dell Inc., and EMC Corporation

IPR Inter partes review petition

LAG Link aggregation group

m-p-f Means-plus-function

MC-LAG Multi-chassis link aggregation group 

MPEP Manual of Patent Examining Procedure

Plaintiff WSOU Investments, LLC d/b/a Brazos Licensing and Development

PlBr. Opening Claim Construction Brief (Case No. 6:20-cv-00477-ADA, 

Dkt. 80; Case No. 6:20-cv-00482-ADA, Dkt. 76)

POSA Person of ordinary skill in the art

PTAB Patent Trial and Appeal Board

ReplyBr. Reply Claim Construction Brief (Case No. 6:20-cv-00477-ADA, Dkt. 

84; Case No. 6:20-cv-00482-ADA, Dkt. 80)

Emphasis added unless indicated otherwise.

Case 6:20-cv-00477-ADA Document 87 Filed 04/14/21 Page 4 of 11
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I. DISPUTED TERMS FROM THE ’020 PATENT

A. “removing, at the network node, the protocol data of a portion of protocol layers from

the received data stream” (claim 1) / “removes protocol data from a portion of

protocol layers from a data stream” (claim 6)

WSOU’s reply fails to address the fatal flaw with its proposal: the plain and ordinary

meaning of “portion” it propounds (PlBr. 3; ReplyBr. 1)—“data need only be removed in at least

one protocol layer”—was expressly disavowed by applicant. DefBr. 4–5. Incredibly, despite

Defendants’ extensive discussion of the prosecution history that flatly precludes WSOU’s

proposed construction, WSOU does not even attempt to explain the prosecution history or address

the inconsistent statements therein about the scope of the claims. WSOU also does not—and

cannot—offer an alternative formulation of plain meaning that is consistent with that intrinsic

record. The intrinsic record’s inconsistent use of “portion” thus leaves this term indefinite.1

WSOU’s argument that a claim does not need to “inform” a POSA about its scope is

squarely incorrect. ReplyBr. 1. The law “require[s] that a patent’s claims . . . inform [a POSA]

about the scope.” Nautilus, Inc. v. Biosig Instruments, Inc., 572 U.S. 898, 910 (2014). WSOU is

also wrong in arguing that Defendants “confuse breadth with indefiniteness.” ReplyBr. 1. 

Defendants’ argument is not about breadth, but about the claim’s lack of ascertainable boundaries. 

DefBr. 2–3; Union Pac. Res. Co. v. Chesapeake Energy Corp., 236 F.3d 684, 692 (Fed. Cir. 2001)

(definiteness inquiry focuses on whether a POSA would understand scope of the claim and finding

“comparing” indefinite where it “could undoubtedly have other meanings”).

2

1 WSOU cites InterDigital Commc’n, LLC v. Int’l Trade Comm’n, 690 F.3d 1318 (Fed. Cir. 2012)

to argue that modifiers are not added to terms. In InterDigital, the court declined to construe

“code” alone because it was used with several different modifiers. Id. at 1325 n.1. Here, neither

party seeks to add a modifier to “portion,” and the patent does not apply such modifiers.

2

 See also California Inst. of Tech. v. Hughes Commc’ns Inc., 35 F. Supp. 3d 1176, 1194 (C.D.

Cal. 2014) (“[T]hat a term covers broad possibilities does not render it indefinite, as long as a

person of ordinary skill can identify the outer boundaries.”). 

Case 6:20-cv-00477-ADA Document 87 Filed 04/14/21 Page 5 of 11
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Finally, rather than address the substance of the irreconcilable prosecution arguments,

WSOU argues that applicant was not “obligated” to define “portion.” ReplyBr. 1. But Defendants

never argued that applicant needed to define “portion.” Defendants instead showed that applicant

made numerous inconsistent statements about the scope of “portion,” leaving the term hopelessly

ambiguous. It is telling that WSOU does not even attempt to address Defendants’ actual argument. 

B. “a control unit which removes protocol data from a portion of protocol layers from a

data stream received from the communication network via the second interface, the

data stream comprising useful data and the protocol data, and switches a remaining

data stream to be transmitted to one of the terminals via the first interface” (claim 6)

1. The term is indefinite under IPXL

WSOU’s reply ignores that applicant explicitly amended claims from requiring mere

capability to instead requiring performance of steps by the apparatus. DefBr. 6–7. Instead, WSOU

relies on MasterMine Software, Inc. v. Microsoft Corp., to argue that “which removes” reflects

mere capability. 874 F.3d 1307, 1316 (Fed. Cir. 2017). MasterMine, however, stands only for the

proposition that an apparatus claim that recites capability is not IPXL indefinite. It analyzed the

claim language at issue to determine whether it required capability or performance. MasterMine,

874 F.3d at 1313–16. Here, the claim language unambiguously recites actual performance (“which

removes”) within an apparatus claim. DefBr. 6–7. And—unlike in MasterMine—this reading is

compelled by the prosecution history, in which the claims were amended to recite “which

removes” instead of “which is configured to remove.” Id. WSOU ignores these amendments.

Finally, WSOU creates a false dichotomy between a claim involving capability and a claim

involving user action. Contrary to WSOU’s argument, a claim can be invalid under IPXL even if

it does not involve user action, so long as it recites a method step within an apparatus claim. 

Rembrandt Data Techs., LP v. AOL, LLC, 641 F.3d 1331, 1339 (Fed. Cir. 2011). The test is not

whether the claim recites user action but whether it recites a method step—here, claim 6 does.

Case 6:20-cv-00477-ADA Document 87 Filed 04/14/21 Page 6 of 11
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2. Alternatively, the term is subject to 35 U.S.C. § 112, ¶ 6

WSOU’s reply ignores Defendants’ arguments based on the specific language of claim 6

and the ’020 patent. Instead, WSOU argues that “control unit” recites sufficient structure because

Judge Gilstrap determined “control unit” recites sufficient structure in Canon, Inc. v. TCL Elecs.

Holdings Ltd., 2020 WL 2098197, at *15 (E.D. Tex. May 1, 2020). ReplyBr. 3. But Canon is a

different patent, with a different prosecution history, covering different technology—thus, whether

“control unit” or “control” imparted sufficient structure to the Canon POSA, absent a showing that

person is the same as the ’020 POSA (which they are not3

), is irrelevant to whether sufficient

structure exists here. Similarly, that the Canon claim language, which is drastically different than

claim 6, failed to invoke m-p-f is inapposite. Indeed, WSOU’s brief confirms claim 6’s language

only describes functionality. DefBr. 8. Since the term “control unit” is limited only by itsfunction,

it must be construed as m-p-f. Given that WSOU does not contest Defendants’ identification of

corresponding structure, if the term is definite, it should be construed to require Defendants’

proposed structure. 

C. “bus system” (claims 1 and 6) 

WSOU concedes that the specification states the communication network can be a “(a) ‘bus

system’ and (b) ‘[i]t is however also possible’ for communication network KN to include ‘active

components such as switching nodes, gateways, routers, [or] bridges.’” ReplyBr. 4. WSOU

somehow interprets these statements to mean that a bus network may include such active

components, arguing that “there is no suggestion that (a) and (b) were being contrasted.” Id. This

3

 The Canon patent relates to “conventional [tv] broadcasts and internet streaming broadcasts on

a [TV].” Id. at *5. Plaintiff there asserted that a POSA would have a university education and

“two or more years’ work experience with digital [TV] and streaming technology.” Canon, No.

18-cv-546, D.I. 91-9 ¶ 36. The ’020 patent does not discuss digital TV and streaming technology.

Case 6:20-cv-00477-ADA Document 87 Filed 04/14/21 Page 7 of 11
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ignores the use of “however,” which unambiguously contrasts (a) and (b). Baldwin v. New York,

2015 WL 6696505, at *2 (W.D.N.Y. Nov. 2, 2015) (“however” “creat[ed] a contrast”).4

 In other

words, the patent contrasts a communication network that is a “bus network” with one that is not

(i.e., one with “active components”). Thisis exactly how the examiner interpreted these statements

when addressing a “bus system.” DefBr. 10 (quoting Ex. 8).

WSOU attempts to dismiss the prosecution history by stating that applicant’s silence in the

face of the examiner’s interpretation of “bus system” cannot amount to disavowal. ReplyBr. 4. 

While it is not necessary to find disavowal here since the specification clearly distinguishes a “bus

system” from other networks, WSOU nonetheless relies on inapposite law. In 3M Innovative

Props. Co. v. Avery Dennison Corp., 350 F.3d 1365, 1373–74 (Fed. Cir. 2003)—upon which

WSOU relies—the application was allowed on grounds unrelated to the examiner’s

characterization. In contrast, the limitation here was expressly related to patentability. It was

added to overcome prior art. DefBr., Ex. 3 at 2 (adding “bus system”); id., Ex. 3 at 8–9 (arguing

reference “does not teach or suggest that ‘the communication network is a bus system’”). That the

claims were prosecuted expressly based on the interpretation of “bus system” Defendants propose,

is highly germane to claim construction here.

II. DISPUTED TERM FROM THE ’489 PATENT

A. “the first set of port interfaces of the multi-chassis link aggregate” (claims 1, 8, 15)

This term lacks an antecedent basis and is strikingly similar to a term the Federal Circuit 

held to be indefinite. See DefBr. 12–13. Just like the term in Bushnell, a POSA would not have 

understood to which set of port interfaces this term refers. Bushnell Hawthorne, LLC v. Cisco 

Systems, Inc., 813 F. App’x 522 (Fed. Cir. May 14, 2020). WSOU has no answer to this 

4

 Mayes v. E.P.A., 2008 WL 65178, at *16 (E.D. Tenn. Jan. 4, 2008) (“however” is an exception).

Case 6:20-cv-00477-ADA Document 87 Filed 04/14/21 Page 8 of 11
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ambiguity and tellingly ignores the Bushnell case in its reply. ReplyBr. 4–5. Instead, WSOU 

merely parrots its opening brief argument, declaring: “‘the first set of port interfaces’ [] refers 

back to the ‘first set of member port interfaces of the aggregation switch.’” The fundamental 

problem with WSOU’s argument is that this is not what the claims say. The claims refer to “the 

first set of port interfaces of the multi-chassis link aggregate,” not “of the aggregation switch.” 

WSOU effectively seeks to re-write the claims, which is forbidden. K-2 Corp. v. Valomon S.A., 

191 F.3d 1356, 1364 (Fed. Cir. 1999). Adding to the ambiguity, the claims recite sets of “member

port interfaces” when referring to a single aggregation switch, and a set of non-member “port 

interfaces” when referring to the multi-chassis link aggregate. See ’489 patent, cl. 1; Merck & 

Co. v. Teva Pharm. USA, Inc., 395 F.3d 1364, 1372 (Fed. Cir. 2005) (“A claim construction that 

gives meaning to all the terms of the claim is preferred over one that does not do so.”).

WSOU attempts to sidestep this obvious inconsistency in claim language by arguing that 

the first set of port interfaces became a part of the multi-chassis link aggregate when it was 

combined with a set of port interfaces from a remote switch. ReplyBr. 5. This, however, is 

precisely why the term is indefinite: there are three different sets of port interfaces of the multichassis link aggregate to which the claims could be referring: (1) the set from the aggregation 

switch, (2) the set from the remote switch, or (3) the combination of both sets. This lack of clarity 

renders the claims indefinite under Bushnell. See DefBr. 13.5

5

 WSOU also incorrectly argues that Defendants’ IPR somehow precludes any argument that the

claims are indefinite. Claim construction is only performed in the IPR to the extent necessary to

resolve the IPR. Well-man, Inc. v. Eastman Chem. Co., 642 F.3d 1355, 1361 (Fed. Cir. 2011). 

Here, the prior art reference discloses the exact same multi-chassis link aggregation system as in

the ’489 patent. As such, notwithstanding the indefiniteness of the claims, Defendants showed

that the prior art disclosed this limitation based on WSOU’s infringement read. See Spherix Inc.

v. Matal, 703 F. App’x 982, (Fed. Cir. 2017) (affirming the PTAB where the petitioner adopted

the patentee’s claim constructions at the district court).

Case 6:20-cv-00477-ADA Document 87 Filed 04/14/21 Page 9 of 11
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Dated: April 14, 2021 By: /s/ Barry K. Shelton

Barry K. Shelton

Texas State Bar No. 24055029

bshelton@sheltoncoburn.com

SHELTON COBURN LLP

311 RR 620, Suite 205

Austin, TX 78734-4775 

Telephone: 512.263.2165

Facsimile: 512.263.2166 

Benjamin Hershkowitz

bhershkowitz@gibsondunn.com

Brian A. Rosenthal

brosenthal@gibsondunn.com 

Allen Kathir

akathir@gibsondunn.com

Kyanna Sabanoglu

ksabanoglu@gibsondunn.com

GIBSON, DUNN & CRUTCHER LLP

200 Park Avenue

New York, NY 10166-0193 

Telephone: 212.351.4000

Facsimile: 212.351.4035 

Y. Ernest Hsin

ehsin@gibsondunn.com

Jaysen S. Chung

jschung@gibsondunn.com

GIBSON, DUNN & CRUTCHER LLP

555 Mission Street, Suite 3000

San Francisco, CA 94105-0921

Telephone: 415.393.8200

Facsimile: 415.393.8306

Ryan K. Iwahashi

riwahashi@gibsondunn.com

GIBSON, DUNN & CRUTCHER LLP

1881 Page Mill Road

Palo Alto, CA 94304-1211

Telephone: 650.849.5300

Facsimile: 650.849.5333

Attorneys for Defendants

Case 6:20-cv-00477-ADA Document 87 Filed 04/14/21 Page 10 of 11
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CERTIFICATE OF SERVICE

The undersigned certifies that on April 14, 2021, all counsel of record who are deemed to 

have consented to electronic service are being served with a copy of this document through the 

Court’s CM/ECF system under Local Rule CV-5(b)(1). 

/s/ Barry K. Shelton

Barry K. Shelton

Case 6:20-cv-00477-ADA Document 87 Filed 04/14/21 Page 11 of 11