Phenix Longhorn, LLC v. AU Optronics Corporation et al

IN THE UNITED STATES DISTRICT COURT
FOR THE EASTERN DISTRICT OF TEXAS
MARSHALL DIVISION
PHENIX LONGHORN LLC,
Plaintiff,
v.
AU OPTRONICS CORPORATION,
HISENSE ELECTRONICA MEXICO,
S.A. DE C.V., HISENSE USA
CORPORATION, HISENSE VISUAL
TECHNOLOGY CO., LTD., and
DOES 1–10,
Defendants.
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CASE NO. 2:23-CV-00477-RWS-RSP
MEMORANDUM ORDER
Before 	the 	Court 	is 	AUO’s 	Opposed 	O2 	Micro 	Motion 	for 	Further 	Claim
Construction. Dkt. No. 307. The Motion is fully briefed. See Dkt. Nos. 369, 403, 406. AUO
seeks additional claim construction of the term “multiplexer” from Claim 1 of U.S. Patent
No. 7,233,305 (“’305 Patent”) because Phenix is allegedly now satisfying the “circuits for
programming” and “multiplexer” limitation with “I2Cs,” and AUO contends—and Phenix
disputes—that 	there 	must 	be 	some 	“structural” 	boundary 	between 	“circuits 	for
programming” and “multiplexer,” as Claim 1 uses the two terms. See Dkt. No. 307 at 1–2.
Having considered the briefing, for the reasons set forth fully below, the Court finds that the
Motion should be denied.
I. 	LEGAL STANDARD
“District courts are not (and should not be) required to construe every limitation
present in a patent’s asserted claims.” O2 Micro Int’l Ltd. v. Beyond Innovation Tech. Co.,
521 F.3d 1361–62, 1362 (Fed. Cir. 2008). Instead, district courts are to resolve any
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“fundamental dispute regarding the scope of a claim term.” Id. at 1363. “[T]he court, not the
jury, must resolve” such disputes regarding the scope of claims. Id. at 1360.
II. 	DISCUSSION
The claim at issue is Claim 1 of the ’305 Patent, and the limitation at issue is
Limitation 1[b], which recites “circuits for programming coupled to a multiplexer for
addressing and programming said storage cells, wherein the addressing is based on a
plurality of inputs.” ’305 Patent at 7:48–50.
As a threshold matter, AUO argues that the report of Phenix’s expert, Mr.
McAlexander, is insufficient regarding satisfaction of the claimed multiplexer. See Dkt. No.
307 at 6–8. For example, AUO argues that Mr. McAlexander’s report did not identify the
inputs for the multiplexer. See Dkt. No. 403 at 3–4. AUO also argues that Phenix is
attempting to use Mr. McAlexander’s deposition to fill gaps in Mr. McAlexander’s report.
See id. at 3. These arguments, however, are not fundamentally related to the claim scope but
instead relate to sufficiency of Mr. McAlexander’s report and do not bear upon whether any
supplemental claim construction is necessary.
The dispute presented in AUO’s Motion is fundamentally a factual dispute regarding
infringement, which is perhaps most apparent in the last paragraph of AUO’s Statement of
Facts. See Dkt. No. 307 at 9–10. That paragraph states the following:
When asked to identify where he identified a multiplexer in his report, Mr.
McAlexander 	testified 	that 	the 	multiplexer 	is 	“located 	in 	that
communication path between the controller and the nonvolatile memory.”
But he admitted that “the function block diagram itself does not show a
multiplexer.” When pressed, he agreed “the functionality of this function
block would require a multiplexer between the controller and the NVM.”
This testimony stands in contrast with his report, which simply states that
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“AUO’s pgamma ICs also contain ‘a multiplexer’” with no explanation how
this was confirmed or what structure constitutes the multiplexer.
Id. (citations omitted). Likewise, AUO summarizes a portion of Mr. McAlexander’s
deposition testimony, as follows:
Mr. McAlexander testified to a functional allocation that assigns all
addressing work to the “circuits for programming” while limiting the
multiplexer 	to 	a 	routing 	function. 	He 	identified 	the 	“circuits 	for
programming” as the I2C controller and testified these circuits receive the
address, decode it, and “make[] a decision” based on “all of the inputs” and
“all the addresses.” When asked what function the multiplexer performs, he
responded “Steering. The directing.” Mr. McAlexander confirmed the
multiplexer simply acts like a “traffic cop” and is akin to “coming to a . . .
five-road split and you choose which direction you go. The multiplexer
directs the traffic.” He explicitly stated, “the multiplexer is not the one doing
the addressing.” Here, all addressing functions—receiving addressing,
decoding them, making logical decisions—occur within the I2C before the
multiplexer acts. The multiplexer’s sole function is routing the result to the
selected bank.
Id. at 13 (citations omitted). AUO argues that “Mr. McAlexander’s description of the
multiplexer ‘steering’ to banks actually corresponds to the bank selection function
performed by B0–B2, which is separately claimed in [Limitation] 1[h],” id. at 13, but Phenix
responds that Mr. McAlexander identifies different structure for bank selection, see Dkt. No.
369 at 9 (citing Dkt. No. 369-4 at 101:10–102:25). This dispute pertains to the infringement
analysis, not the scope of the claim language.
The 	briefing 	further 	demonstrates 	factual 	disputes 	regarding 	infringement,
particularly as to whether Phenix has identified any “multiplexer” that works together with
“circuits for programming,” so as to perform addressing and programming, as claimed. See,
e.g., Dkt. No. 369 at 4 (“A multiplexer coupled to the I2C interface in the accused pgamma
ICs satisfies the ‘multiplexer’ limitation, consistent with the Court’s construction of the term,
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as the multiplexer routs the addressing and programming data from the ‘circuits for
programming’ to the storage cells.”). But Phenix’s understanding of the claim is reinforced
by disclosure in the specification regarding a “programming engine” working together with
a “mux” (multiplexer), as shown in the following excerpt therefrom:
The programming engine 310, coupled to the mux, comprises an Analog
Input which will be used to set the reference voltage level and a R/W control
signal for a corresponding gamma reference controller. The mux 320
connects signals from the programming engine 310 to any one of the
programmable 	analog 	floating 	gate 	memory 	cells 	330 	through 	337,
depending on three address inputs (A0, A1, and A2). Address inputs are
used to select which cell is being written to at any time.
’305 Patent at 3:52-4:3.
Finally, AUO does not propose a construction of the allegedly disputed multiplexer
term. Instead, AUO merely suggests that “the Court should find that the multiplexer must
play some role in addressing.” See Dkt. No. 307 at 15 (emphasis added); see also Dkt. No.
403 	at 	5 	(“request[ing] 	that 	the 	Court 	construe 	multiplexer 	to 	require 	addressing
functionality.”). It is unclear to the Court what role in addressing AUO proposes the
multiplexer plays. The lack of any specific proposed construction underscores this Court’s
finding that AUO’s Motion is essentially seeking a factual finding of non-infringement. The
Court thus finds that AUO’s Motion should be and hereby is DENIED.
III. 	CONCLUSION
Accordingly, for the reasons and to the extent set forth fully above, the Court finds
that the Motion should be and hereby is DENIED.
.
____________________________________
ROY S. PAYNE
UNITED STATES MAGISTRATE JUDGE
SIGNED this 3rd day of January, 2012.
SIGNED this 14th day of January, 2026.
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