IN THE UNITED STATES DISTRICT COURT

FOR THE EASTERN DISTRICT OF TEXAS

MARSHALL DIVISION

HEADWATER RESEARCH LLC,

Plaintiff,

vs.

AT&T INC., AT&T SERVICES, INC., AT&T 

MOBILITY, LLC AND AT&T CORP.,

Defendants.

Civil Action No. 2:23-cv-00398-JRG-RSP

(Member Case)

ANSWER TO COUNTERCLAIMS

JURY TRIAL

Civil Action No. 2:23-cv-00397-JRG-RSP

(Lead Case)

ANSWER TO COUNTERCLAIMS

JURY TRIAL

HEADWATER RESEARCH LLC,

Plaintiff,

vs.

AT&T INC., AT&T SERVICES, INC., AT&T 

MOBILITY, LLC AND AT&T CORP.,

Defendants.

HEADWATER’S ANSWER TO AT&T’S COUNTERCLAIMS 

Plaintiff and Counterclaim-Defendant Headwater Research LLC (“Headwater”) hereby 

answers Defendants and Counterclaimant-Plaintiffs’ AT&T Services, Inc., AT&T Mobility, LLC, 

AT&T Corp. (collectively, “AT&T” or “Counterclaimants”), counterclaims as follows:

THE PARTIES

1. Headwater does not have knowledge or information sufficient to form a belief as to

the truth of the allegations contained in Paragraph 1 and on that basis: denied.

2. Headwater does not have knowledge or information sufficient to form a belief as to

the truth of the allegations contained in Paragraph 2 and on that basis: denied.

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3. Headwater does not have knowledge or information sufficient to form a belief as to 

the truth of the allegations contained in Paragraph 3 and on that basis: denied.

4. Admitted that Headwater Research LLC is a Texas limited liability company with 

its headquarters at 110 North College Avenue, Suite 1116, Tyler, Texas 75702.

JURISDICTION AND VENUE

5. Admitted.

6. Admitted.

7. Admitted.

8. Headwater admits that it has sued AT&T for infringement of the ’543 Patent, and 

’042 Patent and that there is a substantial, actual, and continuing controversy between Headwater

and AT&T as to the infringement of the asserted patents. Headwater denies the remaining 

allegations of paragraph 8.

COUNT I

(Declaratory Judgment of Invalidity of the ’543 Patent)

9. Headwater incorporates the preceding paragraphs by reference, as though fully set 

forth herein.

10. Denied.

11. Denied.

COUNT II

(Declaratory Judgment of Invalidity of the ’042 Patent)

12. Headwater incorporates the preceding paragraphs by reference, as though fully set 

forth herein.

13. Denied.

14. Denied.

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JURY DEMAND

15. Headwater, under Rule 38 of the Federal Rules of Civil Procedure, requests a trial 

by jury of any issues so triable by right.

EXCEPTIONAL CASE

16. Denied.

PRAYER FOR RELIEF

In response to AT&T’s prayer for relief, Headwater denies that AT&T is entitled to any 

relief, including any of the relief requested in paragraphs A–D of AT&T’s prayer for relief. Further, 

Headwater requests the following relief:

WHEREFORE, Headwater respectfully requests that this Court enter:

a. A judgment in favor of Headwater that AT&T has infringed, either directly or 

indirectly, literally, under the doctrine of equivalents, or otherwise, the’541 Patent and the ’613

Patent;

b. A permanent injunction prohibiting AT&T from further acts of infringement of 

the ’543 Patent and the ’042 Patent;

c. A judgment and order requiring AT&T to pay Headwater its damages, enhanced 

damages, costs, expenses, and pre-judgment and post-judgment interest for AT&T’s infringement 

of the’543 Patent and the ’042 Patent;

d. A judgment and order requiring AT&T to provide accountings and to pay 

supplemental damages to Headwater, including without limitation, pre-judgment and postjudgment interest;

e. A judgment and order finding that this is an exceptional case within the meaning 

of 35 U.S.C. § 285 and awarding to Headwater its reasonable attorneys’ fees against AT&T; and

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f. Any and all other relief as the Court may deem appropriate and just under the 

circumstances.

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Dated: December 4, 2023 Respectfully submitted,

/s/ Marc Fenster

Marc Fenster

CA State Bar No. 181067

Email: mfenster@raklaw.com

Reza Mirzaie

CA State Bar No. 246953

Email: rmirzaie@raklaw.com

Brian Ledahl

CA State Bar No. 186579

Email: bledahl@raklaw.com

Ben Wang

CA State Bar No. 228712

Email: bwang@raklaw.com

Dale Chang

CA State Bar No. 248657

Email: dchang@raklaw.com 

Paul Kroeger

CA State Bar No. 229074

Email: pkroeger@raklaw.com

Neil A. Rubin

CA State Bar No. 250761

Email: nrubin@raklaw.com

Kristopher Davis

CA State Bar No. 329627

Email: kdavis@raklaw.com

James S. Tsuei

CA State Bar No. 285530

Email: jtsuei@raklaw.com

Philip Wang

CA State Bar No. 262239

Email: pwang@raklaw.com

Amy Hayden

CA State Bar No. 287026

Email: ahayden@raklaw.com

Jason M. Wietholter

CA State Bar No. 337139

Email: jwietholter@raklaw.com

RUSS AUGUST & KABAT

12424 Wilshire Blvd. 12th Floor

Los Angeles, CA 90025

Telephone: 310-826-7474

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ATTORNEYS FOR PLAINTIFF AND 

COUNTERCLAIM-DEFENDANT,

Headwater Research LLC

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CERTIFICATE OF SERVICE

I hereby certify that all counsel of record who are deemed to have consented to electronic 

service are being served this 4th day of December 2023, with a copy of this document via the 

Court’s CM/ECF system per Local Rule CV-5(a)(3).

/s/ Marc Fenster

Marc Fenster

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