Longitude Licensing Limited v. BOE Technology Group Co., Ltd.

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IN THE UNITED STATES DISTRICT COURT
FOR THE EASTERN DISTRICT OF TEXAS
MARSHALL DIVISION
LONGITUDE LICENSING LIMITED and
138 EAST LCD ADVANCEMENTS
LIMITED,
Plaintiffs,
v.
BOE TECHNOLOGY GROUP CO.,
LTD.,
Defendant.
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CASE NO. 2:23-CV-00515-JRG-RSP
MEMORANDUM ORDER
Before the Court is Defendant’s Motion to Exclude Portions of Dr. E. Fred Schubert’s
Testimony Regarding Infringement. Dkt. No. 187. The Motion is ripe. See Dkt. Nos. 201, 218.
Additionally, the Parties submitted supplemental briefing, see Dkt. Nos. 299, 300, in response to
the Court’s order, see Dkt. No. 266. Dr. Schubert is Plaintiffs’ technical expert, and opines on,
inter alia, validity, infringement, use, and benefits of the ’079, ’948, ’093, ’157, ’606, and ’462
Patents. See Op. Rep., Dkt. No. 187-2; First Supp. Rep., Dkt. No. 187-4; Second Supp. Rep., Dkt.
No. 299-1; Validity Rep., Dkt. No. 187-3. In the Motion and supplemental briefing, Defendant
seeks to exclude (1) portions of Dr. Schubert’s Opening Report as inconsistent with this Court’s
Claim Construction Order, see Claim Constr. Order, Dkt. No. 129; (2) portions of his First and
Second Supplemental Reports under Federal Rule of Evidence 702 and Daubert v. Merrell Dow
Pharms., Inc., 509 U.S. 579 (1993); and (3) portions of his Validity Report under Federal Rule of
Civil Procedure 37 for untimely addition of an infringement theory. See Dkt. No. 187; Dkt. No.
299. For the reasons set forth below, the Court denies the Motion.
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I. 	LEGAL STANDARD
An expert witness may provide opinion testimony if “(a) the expert’s scientific, technical,
or other specialized knowledge will help the trier of fact to understand the evidence or to determine
a fact in issue; (b) the testimony is based on sufficient facts or data; (c) the testimony is the product
of reliable principles and methods; and (d) the expert has reliably applied the principles and
methods to the facts of the case.” Fed. R. Evid. 702.
Rule 702 requires trial courts to make a preliminary determination, when requested, as to
whether the requirements of the rule are satisfied regarding a particular expert’s proposed
testimony. See Kumho Tire Co. v. Carmichael, 526 U.S. 137, 149 (1999); Daubert, 509 U.S. at
592–93 (1993). Such courts are given broad discretion in making Rule 702 admissibility
determinations. Kumho Tire, 526 U.S. at 152 (“[A] judge must have considerable leeway in
deciding in a particular case how to go about determining whether particular expert’s testimony is
reliable”). Although the Fifth Circuit and other courts have identified various factors that the court
may consider in determining whether an expert’s testimony should be admitted, the nature of the
factors that are appropriate for the court to consider is dictated by the ultimate inquiry—whether
the expert’s testimony is sufficiently reliable and relevant to be helpful to the finder of fact and
thus to warrant admission at trial. See United States v. Valencia, 600 F.3d 389, 424 (5th Cir. 2010).
Importantly, in a jury trial setting, the Court’s role under Daubert is not to weigh the expert
testimony to the point of supplanting the jury’s fact-finding role; instead, the Court’s role is limited
to that of a gatekeeper, ensuring that the evidence in dispute is at least sufficiently reliable and
relevant to the issue before the jury that it is appropriate for the jury to consider. See Micro Chem.,
Inc. v. Lextron, Inc., 317 F.3d 1387, 1391–92 (Fed. Cir. 2003) (applying Fifth Circuit law) (“When,
as here, the parties’ experts rely on conflicting sets of facts, it is not the role of the trial court to
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evaluate the correctness of facts underlying one expert’s testimony.”); Pipitone v. Biomatrix, Inc.,
288 F.3d 239, 249–50 (5th Cir. 2002) (“‘The trial court’s role as gatekeeper [under Daubert] is not
intended to serve as a replacement for the adversary system.’ . . . Thus, while exercising its role as
a gate-keeper, a trial court must take care not to transform a Daubert hearing into a trial on the
merits” (quoting an Advisory Committee Note to Fed. R. Evid. 702)). As the Supreme Court
explained, 	“[v]igorous 	cross-examination, 	presentation 	of 	contrary 	evidence, 	and 	careful
instruction on the burden of proof are the traditional and appropriate means of attacking shaky but
admissible evidence.” See Mathis v. Exxon Corp., 302 F.3d 448, 461 (5th Cir. 2002).
Despite the above, however, “[e]ven if testimony is reliable, it may still be excluded if it
relies on information that violates the [Federal] [R]ules [of Civil Procedure].” Estech Sys. IP, LLC
v. Carvana LLC, 2023 WL 3292881, at *2 (E.D. Tex. May 5, 2023).
II. 	DISCUSSION
As explained above, Defendant raises several grounds for exclusion of Dr. Schubert’s
reports. The Court addresses each in turn.
A. Exclusion Under Rule 37 of Dr. Schubert’s Validity Report Opinions About Infringement
of the ’948 Patent Under the Doctrine of Equivalents (“DOE”)
According to Defendant, Dr. Schubert’s analysis in his validity report as to a hypothetical
claim should be excluded under Rule 37(c)(1) as untimely under Federal Rule of Civil Procedure
26(a)(2). Dkt. No. 187 at 10 (citing Validity Rep., Appx. XI ¶¶ 62–71). However, Plaintiffs respond
that they “do not intend to offer Dr. Schubert’s hypothetical claim analysis opinions at trial because
BOE waived any ensnarement defense” by not raising or articulating it to the ’948 Patent DOE
theory, Dkt. No. 201 at 15, and, in reply, Defendant “agrees that this issue is rendered moot,” Dkt.
No. 218 at 5. The Court thus DENIES as MOOT the Motion on this ground.
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B. Exclusion of Dr. Schubert’s Opening Report Opinions That Are Allegedly Inconsistent
with the Court’s Claim Construction Order
Defendant next argues that Dr. Schubert’s Opening Report opinions concerning the
“rubbing direction” of the ’948 and “a channel area that extends in a direction” of the ’079 Patent
should be excluded because they are inconsistent with the Court’s Claim Construction Order. Dkt.
No. 187 at 9. Beginning with the first term, the Court defined the term “rubbing direction” as
meaning “a direction created by the rubbing process.” Claim Constr. Order at 16. Some additional
context is useful in resolving this dispute. The Parties previously explained, as recited in the Claim
Construction Order, that “the rubbing process is a well-known mechanical process in liquid crystal
technology similar to brushing that leaves grooves in the rubbed material that cause the liquid
crystal molecules to align along the grooves and, thus, sets the rubbing direction.” Id. at 15. During
claim construction, Plaintiffs argued that “rubbing direction” took on some default alignment
direction, independent of any specific process used to set the alignment direction (i.e., independent
of a rubbing process). Id. at 12. The Court expressly rejected this argument, finding that “rubbing
direction” was not divorced from the “rubbing process,” but instead was a direction caused by it.
Id. at 15–16. This construction was essentially the one for which Defendant advocated. Id. at 13.
According to Defendant, Dr. Schubert’s opinion on “‘the direction along which the color
shifts towards blue’ in polarization tests performed on the accused product,” is inconsistent with
the Court’s definition. Id. at 10 (first citing Op. Rep., Appx. XII ¶¶ 58–62, 124–28, 185–89, 256–
60; and then citing Claim Constr. Order at 12–16). Plaintiffs respond that the Court’s definition
requires both a “direction” and a “rubbing process.” Dkt. No. 201 at 13. They then contend that
Dr. Schubert explained in his Opening Report that BOE uses a rubbing process to set the rubbing
direction for each of the Accused Products. Id. at 13–14 (citing Op. Rep., Appx. XII ¶¶ 52–53,
120–23, 183–84, 190–95, 251–55). According to Plaintiffs, Dr. Schubert only used the polarization
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tests, which Defendant took out of context, to measure and confirm the direction caused by the
rubbing process (i.e., the “rubbing direction”). Having reviewed the cited portions of Dr.
Schubert’s report, the Court agrees that Dr. Schubert’s opinions using the “rubbing direction” with
respect to the ’948 Patent are consistent the Court’s Claim Construction Order. Accordingly, the
Court finds that the Motion on this ground should be and hereby is DENIED.
With respect to the second term, “a channel area that extends in a direction” from the ’079
Patent, the Court defined that term as meaning “a channel length that runs between source and
drain electrodes.” Claim Constr. Order at 12. The Court found that the term “‘channel length’
provide[d] more clarity than ‘channel area’ because the [P]arties both referred to it as such and the
specification also identifies the channel area as being a channel length . . . as well as having a
defined direction.” Id. at 11. The Court also noted that “[t]he direction of the channel length is
along the axis running between the source and drain electrode of the TFT, which is also generally
the direction of current flow.” Id.
Defendant takes issue with Dr. Schubert’s use of “the supposed direction of current flow
rather than the channel length that runs between the source and drain electrodes to determine the
extension of the channel area.” Dkt. No. 187 at 10 (first citing Op. Rep., Appx. XI ¶¶ 10–11; and
then citing Claim Constr. Order at 10–11). Plaintiffs respond that Dr. Schubert explained that “the
[channel] length runs between the source and drain electrodes [because that] is the direction of
current flow in the [A]ccused [P]roduct, concluding ‘[t]he axis along which the channel length
“runs”’ is the vertical axis.” Dkt. No. 201 at 14 (citing Op. Rep., Appx. XI ¶ 10–11). Similarly,
here, having reviewed the cited portions of Dr. Schubert’s Opening Report, the Court does not find
his analysis of the “a channel area that extends in a direction” term from the ’079 Patent to be
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inconsistent with the Court’s construction of it. Therefore, the Court finds that the Motion on this
ground should be and hereby is DENIED.
C. Exclusion Under Daubert of Dr. Schubert’s First and Second Supplemental Report
Opinions About Reasonable Similarity of Additional BOE Products
In the Motion, Defendant argues that Dr. Schubert’s reasonable similarity opinions from
his First Supplemental Report “fall short of providing . . . scientific analysis backed by adequate
facts” for four reasons. Dkt. No. 187 at 5. Defendant repeats the same four arguments in its
supplement in response to Dr. Schubert’s Second Supplemental Report, so the Court only recites
them once although the Court analyzes the arguments with respect to the portions of each report
cited in each set of briefs. Dkt. No. 299 at 1 (citing Second Supp. Rep. ¶¶ 23–28, 31–35, 39–45,
47–50, 52–55, 57–60, 62–65).
Defendant first argues that Dr Schubert “fails to address certain claim limitations [or] show
that the original and additional BOE products share common characteristics . . . to these . . .
limitations.” Id. (citing First Supp. Rep. ¶¶ 20, 27–33, 58–62). Specifically, Defendant points to
the following limitations from the following Asserted Patents: (1) the “a thin-film transistor having
a channel area that extends in a direction,” “the data line having . . . a non-broad portion that does
not overlap the thin film transistor,” “the scanning line having . . . a narrow width portion in another
portion,” and “fixed-potential capacitor electrode” from the ’079 Patent; (2) “rubbing direction”
from the ’948 Patent; and (3) whether the seal region “forming a rectangular shape,” the elements
of “first side,” “second side,” “third side,” and “fourth side,” whether the “pixel region is positions
. . . without protruding from the second substrate in the plan-view of the first substrate,” and
whether the seal member is formed “without the use of a plug,” from the ’606 Patent. Id. (citing
Souri Supp. Rep., Dkt. No. 187-5 ¶¶ 21, 25–26, 44, 46–47).
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The second reason, according to Defendant, is that Dr. Schubert “simply asserts that the
plan-view geometries of the original and additional products are consistent.” Id. at 5–6 (citing First
Supp. Rep. ¶¶ 19–20, 27–33, 41, 51–52, 65–66, 61). Defendant continues that such analysis is
“conclusory” and “unreliable” because Dr. Souri’s analysis confirms that “in some cases, [the
geometries] are markedly different [for] the additional BOE products and/or do not meet the recited
claim limitations.” Id. at 6 (citing Souri Supp. Rep. ¶¶ 26–28, 33, 37).
Defendant’s third argument is that, unlike in his Opening Report, Dr. Schubert “fails to
consider any cross-sectional views for the additional BOE products” in his First Supplemental
Report. Id. at 7. And, Defendant continues, “in the absence of [that analysis], the plan-view GDS
layout files that [he] . . . relies on for the additional BOE products are insufficient to demonstrate
. . . that they share similar cross-sectional features as the” original ones he analyzed. Id. at 8.
Defendant last argues that Dr. Schubert’s opinions in the First Supplemental Report “have
the potential to create” juror confusion because he “fails to identify . . . which additional BOE
products each original [one] is representative of,” so “if the jury finds that some of the original []
products infringe but others do not, they will be left confused as to which additional BOE products
also infringe.” Id. at 8–9. Essentially, Defendant argues that because Dr. Schubert independently
analyzed each product for infringement purposes of each Asserted Patent in his Opening Report,
and then, in his Supplemental Report analyzed the additional products with respect to the original
products he found infringed each Asserted Patent, if the jury were to find infringement of some
subset of the products that infringed an Asserted Patent, they would be confused on whether the
additional products also infringed with Dr. Schubert’s non-individualized reasonable similarity
analysis. Id.
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Plaintiffs respond to each of Defendant’s four arguments fulsomely, both in their original
response, and in their supplemental response. See Dkt. No. 201 at 2–13; Dkt. No. 300 at 1–3. For
each of the three patents to which Defendant points as evidence of its first argument, that Dr.
Schubert did not analyze the infringement of claims, limitation-by-limitation, Plaintiffs quote and
cite to specific language from the report allegedly showing that the claim limitations Defendant
took issue with were analyzed by Dr. Schubert and addressed. Id. at 6–7 (citing First Supp. Rep.
¶¶ 20–24, 36–38, 61).
As to Defendant’s second argument, that Dr. Schubert’s analysis of only the plan-view
geometries was cursory, Plaintiffs respond that Dr. Schubert “provided a complete explanation . .
. regarding similarities among GDS layouts and explained that no material differences exist . . . for
the purposes of . . . infringement.” Id. at 7–8 (citing First Supp. Rep. ¶¶ 19–22, 27–33, 41–47, 51–
55, 59–61, 65–69). Again, for each example that Defendant argues constitutes a marked difference
that Dr. Schubert did not explain (related to the ’948, ’093, and ’157 Patents), Plaintiffs quote and
cite to Dr. Schubert’s alleged explanation of why they are not material to his infringement analysis.
Id. (citing First Supp. Rep. ¶¶ 38, 41–47, 51–56; and then citing Op. Rep. ¶¶ 40–41).
To Defendant’s third argument, about Dr. Schubert’s alleged failure to consider cross-
sectional views in his First Supplemental Report, Plaintiffs respond that Defendant “produced no
cross-sectional view evidence when it produced [the] supplemental GDS files [and] cannot now
hide behind documents and testimony it did not provide.” Id. at 11. Tellingly, Defendant
acknowledges this argument but does not dispute it in its reply. See Dkt. No. 218 at 4. However,
Plaintiffs also argue that no limitation requires cross-sectional information beyond what is
provided by the GDS files, as evidenced by Dr. Souri’s own analysis that also did not analyze
cross-sectional views, and Dr. Schubert “explained in his supplemental report how he could infer
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infringement” without that information. Dkt. No. 201 at 9–11 (first citing Souri Supp. Rep.; and
then citing First Supp. Rep. ¶¶ 20, 27, 41, 44, 61).
To Defendant’s final argument—that jurors will be confused by Dr. Schubert’s original
groupings and later reasonable similarity analysis—Plaintiffs first argue that “[e]ach of the
products analyzed in Dr. Schubert’s [O]pening [R]eport is representative of each of the reasonably
similar products identified in his [First] [S]upplemental [R]eport.” Id. at 12. They also argue that
identifying a group of representative products and comparing another allegedly infringing product
to that group is not improper. Id. at 3, 12.
Having reviewed both Dr. Schubert’s Opening Report, and his First and Second
Supplemental Reports, the Court agrees with Plaintiffs. As to Defendant’s first argument, as it
admits throughout (e.g., “Dr Schubert opines that [the] additional BOE . . . products infringe . . .
because these products have reasonably similar design . . . to the original . . . products that he
analyzed in his [O]pening [R]eport.”), Dr. Schubert’s Supplemental Reports do not exist in a
vacuum—they exist with reference to his Opening Report. This fact is important because
Defendant references Dr. Souri’s analysis with respect to this argument, which, in many instances,
complains that Dr. Shubert’s analysis in his First Supplemental Report does not “explain” the
“elements of” claim limitations. See, e.g., Souri Supp. Rep. ¶ 44 (“Dr. Schubert does not explain .
. . the elements of ‘first side,’ . . . .”). Dr. Schubert does explain these elements in his Opening
Report, which he references. See, e.g., First Supp. Rep., § V. Relevant Legal Principles and Claim
Construction ¶ 12 (“In paragraphs 34[–]53 of my Opening [] Report[,] I describe certain legal
principles I was provided and that I applied in rendering my infringement opinions.”).
Most importantly, however, as Plaintiffs argue, Dr. Schubert did address each claim
limitation in his infringement analysis of the additional products. For example, with respect to the
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limitations that Defendant complained were missing from his analysis of the additional products
infringement of the ‘079 Patent, he opines that he “confirmed that the data line, scanning line, thin
film transistor (TFT) and capacitive lines geometries were consistent with those of the
MV270QUM-N20 LCD Module [he] analyzed in [his] Opening [] Report. . . . [He] confirmed that
the data line and the channel area of the TFT extended in the same direction.” See First Supp. Rep.
¶ 20. He goes on to explain that he confirmed each claim limitation, and how he confirmed it. Id.
Defendant’ second argument is similarly unpersuasive. That Defendant’s own expert found
inconsistent the plan geometries that Dr. Schubert found were consistent, is not a reason to exclude,
but rather an issue ripe for cross-examination. See Freeny v. Murphy Oil Corp., No. 2:13-CV-791,
2015 WL 11089599, at *3 (E.D. Tex. June 4, 2015). Similarly, Defendant’s third and fourth
arguments are also arguments to be resolved by rigorous cross-examination, rather than exclusion.
See Mathis, 302 F.3d at 461. Thus, the Motion is DENIED on these grounds.
III. 	CONCLUSION
Accordingly, for the reasons set forth above, the Motion is DENIED.
.
____________________________________
ROY S. PAYNE
UNITED STATES MAGISTRATE JUDGE
SIGNED this 3rd day of January, 2012.
SIGNED this 4th day of December, 2025.
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