UNITED STATES DISTRICT COURT 

FOR THE EASTERN DISTRICT OF TEXAS 

MARSHALL DIVISION

HEADWATER RESEARCH LLC, 

 Plaintiff, 

 v. 

SAMSUNG ELECTRONICS CO., LTD. and 

SAMSUNG ELECTRONICS AMERICA, 

INC., 

 Defendants. 

Case No. 2:23-cv-00103-JRG-RSP 

JURY TRIAL DEMANDED 

PLAINTIFF HEADWATER RESEARCH LLC’S 

SUR-REPLY IN OPPOSITION TO SAMSUNG’S DAUBERT MOTION AND MOTION 

TO STRIKE EXPERT TESTIMONY OF DR. ANDREAS GROEHN 

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Samsung’s motion to strike should be denied. Samsung’s reply in support of its motion to 

exclude Dr. Groehn’s conjoint survey analysis merely repeats arguments this Court has already 

rejected in Headwater Research LLC v. Samsung Electronics Co., No. 2:22-cv-00422-JRG-RSP, 

2024 WL 4712953 (E.D. Tex. Nov. 7, 2024) (“Headwater I”) and that Headwater has already 

addressed in its opposition in this case. If anything, Samsung’s criticisms go to the weight of the 

evidence, not its admissibility. 

I. Dr. Groehn’s conjoint survey and economic analysis are sufficiently tied to the facts 

of this case. 

As Headwater already explained in its opposition, Dr. Groehn’s conjoint survey and 

subsequent economic analysis measures the economic value of increased battery life, and his 

survey and analysis are sufficiently tied to the facts of this case because increased battery life is 

one of the benefits of the patents-in-suit. Opp’n (Dkt. No. 199) at 9-10. And as Headwater also 

already explained, Stephen Dell—Headwater’s damages expert in this case—then combined Dr. 

Groehn’s measure of economic value of increased battery life with Erik de la Iglesia’s—

Headwater’s technical expert’s—technical analysis to estimate improvement in battery life 

specifically attributable to the push-notifications-related accused features. Id. at 10. In this way, 

Mr. Dell calculated the incremental profit per unit directly attributable to the patented contribution 

to battery life (Ex. 3 ¶¶312-313; Dkt. No. 186-1 ¶¶297-311) and a per unit royalty rate (Ex. 3 

¶¶314-318, 349-362, Attachment 4). Samsung is therefore simply incorrect that Mr. Dell “assumed 

Dr. Groehn’s opinions actually isolated the purported benefit of the patents and the accused 

features.” Reply (Dkt. No. 231) at 1. 

Indeed, in Headwater I, this Court found: 

The Court is further not convinced that Dr. Groehn’s focus on battery life is 

inappropriate. [Headwater’s technical expert] Dr. Wesel provides sufficient 

testimony tying battery life to the asserted claims. While the Court 

in Fractus excluded a conjoint survey focused on internal antennas that did not 

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distinguish between the claimed and unclaimed antenna because it failed to 

measure how consumers value the purported advantages provided by the patented 

technology, here Dr. Groehn’s survey was specifically crafted to focus on the 

battery-saving advantages provided by the patented technology. While there are 

other technologies that can also improve battery life, that does not render Dr. 

Groehn’s focus inappropriate. It will be for [Headwater’s damages expert] Mr. 

Kennedy, Dr. Wesel, and Samsung itself to explore how else battery life can be 

improved and the comparable benefit of the claimed invention. 

2024 WL 4712953, at *4. The same is true here. Here, Mr. de la Iglesia “provides sufficient 

testimony tying battery life to the asserted claims,” and “[i]t will be for Mr. [Dell], [Mr. de la 

Iglesia], and Samsung itself to explore how else battery life can be improved and the comparable 

benefit of the claimed invention.” See id. And Samsung’s reliance on Fractus, SA v. Samsung, No. 

6:09-cv-203-LED-JDL, 2011 WL 7563820 (E.D. Tex. Apr. 29, 2011) (see Reply at 2-3) is 

inapposite here for the same reasons the Court found it inapplicable in Headwater I. See 2024 WL 

4712953, at *4.

Samsung is also incorrect to imply that Dr. Groehn used conjoint survey data alone in his 

incremental profit calculations. See Reply at 1. Rather, as Headwater already detailed in its 

opposition, Dr. Groehn used his conjoint survey data in combination with Samsung financial 

information produced in this case. Opp’n at 6-8. This Court already considered this exact same 

criticism and concluded that “the Court is satisfied that Dr. Groehn is sufficiently familiar with the 

use of conjoint surveys to be permitted to opine on them and their use.” Headwater I, 2024 WL 

4712953, at *3 (emphasis added). Thus, “Samsung’s complaint [goes] to weight, not 

admissibility.” Id.1

1 And it is clear from the face of Dr. Groehn’s report (and even Samsung’s reply) that Dr. Groehn 

did not “assume[] zero costs” in his analysis, as Samsung claims. See Reply at 2 n.1. Rather, in 

Dr. Groehn’s analysis, “Samsung’s marginal costs (MC) are assumed to be constant within the 

relevant ... sales volumes ... because at relatively low changes in volume marginal costs are 

unlikely to change.” Ex. A ¶139. In other words, he assumed constant, not zero marginal costs, 

and also explained that this assumption was unrelated to other costs Samsung has, such as average 

costs and variable costs. Id. & n.81. Dr. Groehn also “assume[d] that the marginal costs do not 

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II. Dr. Groehn’s “battery life” attribute and its levels were sufficiently and appropriately 

defined for survey respondents. 

As already explained in Headwater’s opposition, Dr. Groehn defined “battery life” in his 

survey as “the length in time in hours that a device can operate under battery power after being 

fully charged,” and set forth three levels: (1) “Standard battery life”; (2) “Battery life increased by 

5% under normal usage”; and (3) “Battery life increased by 10% under normal usage.” Ex. A ¶93 

(Figure 17). On reply, Samsung continues to criticize this definition and these levels because what 

“standard battery life” is “varies greatly depending on the user and their individual practices.” 

Reply at 1; see also id. at 3-4. But this criticism misses the point—it is critical the survey taker 

consider what standard battery life is for them for the results to be meaningful. Opp’n at 11-12. 

That is precisely what Dr. Greohn’s approach allowed survey respondents to do. Indeed, this Court 

has already found that “Headwater has put forth a sufficient explanation for using its definition in 

this instance.” Headwater I, 2024 WL 4712953, at *4. Thus, “Samsung’s concern about defining 

‘battery life’ is best left for cross-examination.” Id. 

Dated: November 20, 2024 Respectfully submitted, 

/s/ Amy E. Hayden 

Marc Fenster 

CA State Bar No. 181067 

Reza Mirzaie 

CA State Bar No. 246953 

Brian Ledahl 

CA State Bar No. 186579 

Ben Wang 

CA State Bar No. 228712 

Paul Kroeger 

CA State Bar No. 229074 

Neil A. Rubin 

CA State Bar No. 250761 

Kristopher Davis 

differ [with and without improvements in battery life] because the Feature of Interest is softwarebased rendering its marginal cost of distribution to consumers zero or close to zero.” Id. ¶139. 

Again, this assumption assumes constant, not zero, marginal costs. 

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CA State Bar No. 329627 

James S. Tsuei 

CA State Bar No. 285530 

Philip Wang 

CA State Bar No. 262239 

Amy Hayden 

CA State Bar No. 287026 

James Milkey 

CA State Bar No. 281283 

Jason M. Wietholter 

CA State Bar No. 337139 

James N. Pickens 

CA State Bar No. 307474 

RUSS AUGUST & KABAT 

12424 Wilshire Blvd. 12th Floor 

Los Angeles, CA 90025 

Telephone: 310-826-7474 

headwater@raklaw.com 

Andrea L. Fair 

MILLER FAIR HENRY PLLC 

1507 Bill Owens Parkway 

Longview, TX 75604 

Telephone: 903-757-6400 

andrea@millerfairhenry.com 

ATTORNEYS FOR PLAINTIFF, 

Headwater Research LLC 

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