Oyster Optics, LLC v. Coriant America Inc. et al

Filing 615

MEMORANDUM OPINION AND ORDER -. Signed by District Judge Rodney Gilstrap on 6/21/2018. (ch, )

THE UNITED STATES DISTRICT COURT
FOR THE EASTERN DISTRICT OF TEXAS
MARSHALL DIVISION
OYSTER OPTICS, LLC,
v.
CORIANT AMERICA INC., et al.,

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CASE NO. 2:16-CV-1302-JRG

MEMORANDUM OPINION AND ORDER
Before the Court is Defendants Coriant North America, LLC, Coriant Operations, Inc.,
Coriant (USA) Inc., Infinera Corporation, Alcatel-Lucent USA Inc., Fujitsu Network
Communications, Inc., Cisco Systems, Inc., Huawei Technologies Co., Ltd., and Huawei
Technologies USA Inc. (collectively, “Defendants’”) Motion for Partial Summary Judgment of
Noninfringement Based on the Absence of “Phase Modulation” (Dkt. No. 262).1 Also before the
Court are Plaintiff Oyster Optics, LLC’s (“Plaintiff’s” or “Oyster’s”) Opposition (Dkt. No. 354),2
Defendants’ reply (Dkt. No. 458),3 and Plaintiffs’ sur-reply (Dkt. No. 496). After considering the
briefing and evidence, the Court finds that Defendants’ Motion for Summary Judgment (Dkt.
No. 262) should be DENIED and that the Court’s construction of the term “phase modulate”
should be CLARIFIED.

1

Additional attachments are filed at Dkt. Nos. 265, 266, 267, 268, 276, 277, and 279.

2

Additional attachments are filed at Dkt. Nos. 363, 364, 365, 366, 367, 368, 369, and 370.

3

Additional attachments are filed at Dkt. No. 459.
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I. BACKGROUND
Plaintiff has brought suit alleging infringement of United States Patents No. 6,469,816
(“the ’816 Patent”), 6,476,952 (“the ’952 Patent”), 6,594,055 (“the ’055 Patent”), 7,099,592 (“the
’592 Patent”), 7,620,327 (“the ’327 Patent”), 8,374,511 (“the ’511 Patent”), 8,913,898 (“the ’898
Patent”), and 9,363,012 (“the ’012 Patent”) (collectively, “the patents-in-suit”). (See Dkt. No. 157,
Exs. 1–8.) Plaintiff submits that the patents-in-suit are “generally directed towards systems and
methods for transporting information by modulating light waves transmitted and received across
transparent optical fibers.” (Dkt. No. 157, at 2.)
The Court entered a Claim Construction Memorandum and Order on December 5, 2017.
(Dkt. No. 190.) Of relevance here, the Court construed the term “phase modulate” to mean “alter
the phase of light while keeping the amplitude of the light constant to create an optical signal
having a phase that is representative of data.” (Id., at 18; see id., at 10–18.)
II. LEGAL PRINCIPLES
Summary judgment is proper when “the movant shows that there is no genuine dispute as
to any material fact and the movant is entitled to judgment as a matter of law.” Fed. R. Civ. P.
56(a). Under this standard, “the mere existence of some alleged factual dispute between the parties
will not defeat an otherwise properly supported motion for summary judgment; the requirement is
that there be no genuine [dispute] of material fact.” Anderson v. Liberty Lobby, Inc., 477 U.S. 242,
247–48, 106 S.Ct. 2505, 91 L.Ed.2d 202 (1986). The substantive law identifies the material facts,
and disputes over facts that are irrelevant or unnecessary will not defeat a motion for summary
judgment. Id. at 248. A dispute about a material fact is “genuine” when the evidence is “such that
a reasonable jury could return a verdict for the nonmoving party.” Id. Any evidence must be

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viewed in the light most favorable to the nonmovant. See id. at 255 (citing Adickes v. S.H. Kress
& Co., 398 U.S. 144, 158–59, 90 S.Ct. 1598, 26 L.Ed.2d 142 (1970)).
The moving party has the burden to identify the basis for granting summary judgment and
to supply evidence demonstrating the absence of a genuine dispute of material fact. Celotex v.
Catrett, 477 U.S. 317, 323, 106 S.Ct. 2548, 91 L.Ed.2d 265 (1986). If the moving party does not
have the ultimate burden of persuasion at trial, the party “must either produce evidence negating
an essential element of the nonmoving party’s claim or defense or show that the nonmoving party
does not have enough evidence of an essential element to carry its ultimate burden of persuasion
at trial.” Nissan Fire & Marine Ins. Co., Ltd. v. Fritz Cos., Inc., 210 F.3d 1099, 1102 (9th Cir.
2000).
III. THE PARTIES’ POSITIONS
Defendants argue that there can be no genuine issue of material fact, either literally or under
the doctrine of equivalents, as to whether the accused instrumentalities meet the “phase modulate”
limitation as construed by the Court. Defendants submit that this limitation appears in the
following asserted claims: Claims 1 and 3 of the ’952 Patent; Claims 1, 8, and 11 of the ’055
Patent; and Claims 10, 14, 16, 17, 18, 22, 25, 28, 29, and 33 of the ’327 Patent. (Dkt. No. 262,
at 3.) As to the Court’s construction and the specification disclosures cited in the Court’s Markman
analysis, Defendants have noted as follows: “The asserted patent specifications emphasize that
keeping the amplitude constant provides certain benefits. Keeping the amplitude constant, for
example, makes it easier to detect any changes in amplitude, which the patents teach can be
associated with various problems, such as the presence of an intruder attempting to intercept
communications carried by the light.” (Id., at 1.)

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Defendants submit that, in the accused instrumentalities, each phase shift performed in the
course of phase modulation includes a change in amplitude. (See id., at 1–2 & 4.) Defendants
argue that “Oyster’s theory assumes that the Court’s claim construction does not pertain to the
‘transition’ period between symbols,” and Defendants urge the Court to reject Plaintiff’s
interpretation. (Id., at 8.)
Finally, Defendants argue that Plaintiff’s assertion of the doctrine of equivalents (“DOE”)
lacks sufficient specificity, “Oyster’s experts fail to meaningfully explain how or why the
differences are allegedly insubstantial,” and “the patentee expressly disavowed in the specification
the very scope that Oyster is now attempting to capture with DOE.” (Id., at 13; see id. at 11–13.)
Plaintiff responds that Defendants’ technical documents, as well as the opinions of
Defendants’ own experts, support the opinions of Plaintiff’s expert that the accused
instrumentalities keep the amplitude of the light constant for purposes of the Court’s construction.
(See Dkt. No. 354, at 1; see also id. at 23–24.)
Plaintiff also submits that, during claim construction proceedings, the parties addressed
whether “phase modulation” in the patents-in-suit exclude amplitude modulation, not whether
“phase modulation” precludes any alteration of amplitude at any time. (See id., at 1–2; see also
id. at 10 & 21.) Plaintiff requests that the Court “make clear it only excludes amplitude
modulation, not modulation that might ever include any variation in amplitude.” (Id., at 15.)
Plaintiff urges that “under the right construction of claim scope, Defendants have no argument that
their PSK-systems [(phase-shift-keying systems)] do not ‘phase modulate.’” (Id., at 2.)
Alternatively, Plaintiff argues that “beyond the absence of amplitude modulation, the
accused functionality is designed to modulate the phase of light while keeping the amplitude of
the light constant as to the creation of each optical signal having a phase representative of the data

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. . . .” (Id.; see id. at 6 & 8 (“the amplitude is constant whenever the optical signal is actually
representative of the data”); see also id. at 19–21.)
Finally, as to the doctrine of equivalents, Plaintiff responds that the purportedly conclusory
expert opinions criticized by Defendants are sufficient by themselves and, moreover, “plainly refer
to other testimony in [Plaintiff’s expert’s] report in which he explains, in many pages of additional
detail, the transmission, encoding, and optical-data receiving operation in the accused products.”
(Id., at 25.)
Defendants reply that “it is beyond dispute that amplitude in the accused systems is
continuously changing whenever phase is changing, and this change is not some de minimis part
of the accused modulation.” (Dkt. No. 458, at 1.) Defendants submit that, in the accused
instrumentalities, “[t]he process of modulation involves intentionally changing the amplitude . . .
all the way to zero amplitude and then bringing it back up . . . .” (Id., at 7.) Defendants argue that
“the patents never discuss alternative implementations of phase shift keying that rely on amplitude
changes to effect modulation (such as the versions accused in Defendants’ systems).” (Id., at 5.)
Further, Defendants assert that “[i]f used in the system of the patents, the energy level detector
would detect different values of energy (due to different amplitude values), depending on any
particular sequence of data.” (Id., at 8 (citing ’327 Patent at 4:39–47 & ’592 Patent at 2:41–44 &
2:63–3:3).)
As to the doctrine of equivalents, Defendants reply that “there is no analysis or opinion in
Oyster’s reports as to the impact of the changing amplitude in Defendants’ optical signals to the
ability of Defendants’ products to detect drops in amplitude of a phase modulated signal, as
required by every asserted claim of the ’327 Patent.” (Dkt. No. 458, at 10.)

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In sur-reply, Plaintiff argues that it “correctly interprets the Court’s construction based on
what the Court found was actually disparaged by [the] patentee—amplitude modulation—and
consistent with the Defendants’ earlier representation to the Court that a PSK signal whose
amplitude varied during transitions was ‘phase modulation.’” (Dkt. No. 496, at 1.) Plaintiff
submits, for example, that “the amplitude is constant when the phase of the data symbol changes
sufficiently to be representative of the data.” (Id., at 10 (emphasis omitted).) Plaintiff proposes:
To prevent this legal dispute or Defendants’ erroneous interpretation from going to
the jury, Oyster respectfully proposes that this Court either: (a) provide a
supplemental instruction that makes clear “phase modulate” excludes amplitude
modulation but no more; or else (b) provide a revised construction that reflects the
Court’s reasoning and leaves no room to [sic] further misinformation: “alter the
phase of light to create an optical signal having a phase representative of the data,
but not an amplitude representative of the data.”
(Id., at 8 n.2.)
IV. ANALYSIS
During claim construction proceedings, the parties submitted the following proposed
constructions for the term “phase modulate”:
Plaintiff’s Proposed Construction

Defendants’
Proposed
(emphasis added)

Construction

“alter the phase of light to create an optical “alter the phase of light while keeping the
signal having a phase that is representative of amplitude of the light constant to create an
data”4
optical signal having a phase that is
representative of data”
(Dkt. No. 157, at 8; Dkt. No. 165, at 10; Dkt. No. 168, Ex. B, at 1–2, 9, 15, 21, 23, 25, 31 & 35.)
Thus, the only difference between the parties’ proposals was Defendants’ proposal of “while

Plaintiff previously proposed: “No construction necessary. In the alternative, if construed: alter
the phase of light to create an optical signal having a phase that is a function of data.” (Dkt.
No. 145, at 4.)
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keeping the amplitude of the light constant.”

The Court adopted Defendants’ proposed

construction. (Dkt. No. 190, at 18.)
As discussed above, the parties now dispute whether this construction precludes any
change in amplitude during phase modulation or, instead, merely excludes amplitude modulation.
An analysis of Defendants’ motion from a perspective of claim construction is therefore necessary
in order to resolve the parties’ dispute. See O2 Micro Int’l Ltd. v. Beyond Innovation Tech. Co.,
Ltd., 521 F.3d 1351, 1362 (Fed. Cir. 2008) (“When the parties present a fundamental dispute
regarding the scope of a claim term, it is the court’s duty to resolve it.”). Legal principles regarding
claim construction are set forth in the Claim Construction Memorandum and Order. (See Dkt.
No. 190, at 4–8.)
As a threshold matter, the parties appear to agree that amplitude modulation is something
more than merely altering amplitude. (See Dkt. No. 369, Ex. A, Defs.’ Technology Tutorial, at 18
(“Amplitude modulation (amplitude-shift keying (ASK)) works by modulating the amplitude of
the wave depending on the binary electrical data signal.”).)5 Also, the parties appear to agree that
the accused instrumentalities do not use amplitude modulation. (See, e.g., Dkt. No. 364, Ex. OYSINF-A, at 3 (INF0017530) (“[i]t is the phase of the light that is modulated, not the amplitude”).)
Defendants have asserted that “Plaintiff’s contention that ‘amplitude modulation’ is limited to
just those alterations of light that represent data is . . . inconsistent with the intrinsic evidence,”
and Defendants have cited disclosure regarding a “phase modulator” in the receiver in the ’952
Patent. (Dkt. No. 458, at 5 (citing ’952 Patent at 6:56–7:15, 7:16–20, 7:26–33 & Fig. 9.) This
argument, however, appears to be inconsistent with Defendants’ position as set forth in its
technology tutorial. (See Dkt. No. 369, Ex. A, at 7 (“‘Modulation of a wave’ means changing a
wave in order to represent data.”); see also id., at 18 (“Amplitude modulation (amplitude-shift
keying (ASK)) works by modulating the amplitude of the wave depending on the binary electrical
data signal. With amplitude modulation, the power of the signal jumps between, e.g., 100%
(maximum light) and 0% (no light) depending on the bit being transmitted.”).) Further,
interpreting “modulation” in terms of representing data is consistent with Defendants’ own
proposed construction for the term “phase modulate.” Indeed, this portion of the construction was
agreed-upon by both sides during claim construction proceedings.
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Defendants have asserted that “in construing ‘phase modulate’ to mean ‘keeping the
amplitude . . . constant,’ the Court found that the patentee had disavowed claim scope that would
cover amplitude variations.” (Dkt. No. 262, at 9 (citing Dkt. No. 190, at 16–17).) Yet, what the
Court found was “the specification explains that the desired benefits of phase modulation are
obtained only in the absence of amplitude modulation,” not merely “variations” as Defendants
have asserted. (Dkt. No. 190, at 17 (emphasis modified).) In the final paragraph of its analysis,
the Court concluded: “Thus, on balance, in light of the disparagement of prior art involving
amplitude modulation, and in light of the disclosures of the advantages of using phase modulation
instead of amplitude modulation, the ‘phase modulate’ terms should be interpreted so as to exclude
amplitude modulation.” (Dkt. No. 190, at 17.) The Court then adopted Defendants’ proposed
construction. (Id., at 18.)
Also of note, in their responsive claim construction brief, Defendants argued for excluding
amplitude modulation, and Defendants referred to Plaintiff’s concern about other changes in
amplitude as a “red herring”:
Finally, Plaintiff makes an “excluded embodiments” argument. Pl. Br. at 10.
Plaintiff’s argument is that if you boost or reduce the power of the transmitter’s
laser, that consequentially changes the amplitude of the phase modulated signal,
which Plaintiff argues is not allowed by Defendants’ construction. The argument
is a red herring. The terms at issue go to the format of the modulation, based on the
security implications of varying amplitude with data—not whether the power of the
phase modulated signal is adjusted by adjusting the power on the source laser.
(Dkt. No. 165, at 16 (emphasis added).)
Thus, by adopting the Defendants’ proposed construction,6 the Court resolved the dispute
presented by the parties as to whether amplitude modulation should be excluded from the scope of

Defendants have repeatedly referred to this construction as “the Court’s construction” (see, e.g.,
Dkt. No. 262, at 1, 2 & 7), which indeed it was, but the relevant inquiry is what the Court
understood this language to mean (as reflected by the Court’s analysis in the Claim Construction
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“phase modulate.” Defendants have not demonstrated that the dispute presented was otherwise or
that the Court expressed any intent to find a broader disclaimer. Indeed, the construction proposed
by Defendants, which the Court adopted, refers to creating an “optical signal having a phase that
is representative of the data.”7
The Court therefore CLARIFIES the Court’s construction of “phase modulate” as
follows: “alter the phase of light to create an optical signal having a phase that is
representative of data. Use of phase modulation excludes use of amplitude modulation.”
The evidence cited by Plaintiff, such as the following, comports with the Court’s
understanding in this regard and also demonstrates genuine issues of material fact as to
infringement, which precludes summary judgment.
Defendants stated in their Technology Tutorial as part of claim construction proceedings
in the present case that “[w]ith phase modulation, the power is constant regardless of the binary
electrical data signal.” (Dkt. No. 369, Ex. A, at 19; see id., at 22 (“As these slides have shown,
the average power for the ASK [(amplitude-shift keying)] modulated system changes with the
binary electrical data signal, but the power does not change in the PSK modulated system.”) The
specification disclosures cited by Defendants do not show otherwise. See ’327 Patent at 4:39–47

Memorandum and Order), not what Defendants may have tacitly intended it to mean. Although
Defendants’ intent and litigation strategy are not presently at issue, litigants should be mindful that
the resources of the parties and the Court are best utilized by presenting and resolving legal
questions of claim construction during the claim construction proceedings provided by the Court’s
Local Patent Rules (rather than through later motion practice regarding factual issues).
The parties’ arguments regarding the meaning of the word “constant,” which appears in the
construction that the Court adopted, need not be considered because the Court herein clarifies its
construction of the term “phase modulate.” In other words, there is no need to construe the
construction. Rather, the Court herein resolves the parties’ dispute by clarifying the construction
in a manner consistent with the Court’s intent as reflected by the analysis set forth in the Court’s
Claim Construction Memorandum and Order.
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(“The phase-modulated signals have the advantage that breach detection by the energy level
detector work more effectively, since the amplitude of the optical signal is constant and thus a drop
in the optical signal level is more easily detected.”); see also ’592 Patent at 2:41–44 (“The present
invention thus permits a card-based phase-modulated transmission system, which can provide for
more secure data transmission than existing amplitude-based cards.”) & 2:63–3:3 (“the energy
level read by the detector should be constant”).
Also, Plaintiff has submitted technical documents in which Defendants refer to phase
modulation systems in terms of phase shifts rather than in terms of any amplitude variations. (See
Dkt. No. 364, Ex. OYS-INF-A, at 22 (INF0017549) (referring to “[t]he ‘constant-power’ pattern
of QPSK signal (where all symbols have the same power)”); see also id., at 3 (INF0017530) (“It
is the phase of the light that is modulated and carries the information to be transmitted, not the
amplitude.”); id., at 4 (INF0017531) (referring to QPSK as “[f]our-level phase shift modulation”
and contrasting with “[s]tandard two-level amplitude modulation”); Dkt. No. 363, Ex. OYS-FNCA, at 1 (“DP-QPSK is a phase-modulation system that transmits 2-bit signals represented by four
phases on two orthogonally polarized light beams respectively.”); Dkt. No. 365, Ex. OYS-ALUA, at 4 (referring to DPSK and DQPSK as “phase modulation”); Dkt. No. 366, Ex. OYS-HW-A,
at 2588 (HW0021159) (discussing BPSK); Dkt. No. 367, OYS-COR-A, at COR-OYS-0044685
(“In DQPSK . . . two bits are Gray encoded in the phase difference between two consecutive
transmit symbols . . . . The signal constellation consists of four points with constant amplitude and
equidistant phases . . . .”).)
Further, Plaintiff’s experts have opined that phase modulation may involve transient
variations in amplitude that are not involved in representing data but rather that may result from
technical limitations in practical implementations. (See Dkt. No. 363, Ex. OYS-FNC-B, Jan. 10,

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2018 Tonguz Report (Fujitsu), at ¶¶ 111–17; see also Dkt. No. 364, Ex. OYS-INF-C, Jan. 10, 2018
Tonguz Report (Infinera), at ¶¶ 78–83; Dkt. No. 368, Ex. OYS-ALU-C, Jan. 10, 2018 Dallesasse
Report (Alcatel-Lucent), at ¶¶ 103–08; Dkt. No. 366, Ex. OYS-HW-C, Jan. 10, 2018 Tonguz
Report (Huawei), at ¶¶ 82–86; Dkt. No. 368, Ex. OYS-COR-C, Jan. 10, 2018 Dallesasse Report
(Coriant), at ¶¶ 197–202; Dkt. No. 368, Ex. OYS-CIS-B, Jan. 10, 2018 Dallesasse Report (Cisco),
at ¶¶ 131–36; see, e.g., Dkt. No. 279, Feb. 18, 2018 Tonguz dep. at 82:2–5 (“in any real system
there is a transition period where the transmitted light is somewhere between one symbol and the
next”).)
One of Defendants’ experts, Dr. George Papen, also appears to have acknowledged this in
the course of presenting opinions as to invalidity:
59. I also understand that the court has construed “phase modulation” to mean
phase modulation while maintaining a constant amplitude. While I do not believe
that the typical current practice to generate BPSK, QPSK, QAM, or many other
currently implemented transmission techniques satisfies this definition because the
amplitude of the lightwave is typically not held constant when the phase is changed
at bit transitions, I understand that Oyster contends they do. So, as advised by
counsel and solely for purpose of this report, to the extent Oyster contends that
these transmission techniques satisfy the construction of phase modulation, I will
apply that definition to the prior art.
(Dkt. No. 369, Ex. C, Papen Report, at ¶ 59 (emphasis added).)
Plaintiff has likewise cited deposition testimony in which one of Defendants’ experts,
Dr. John Buck, has agreed that phase modulation may, in practical use, involve some variations in
amplitude, such as when using a “Mach-Zehnder” modulator8:
Q So if I’m understanding your testimony just now, are you saying that when you
use a Mach-Zehnder phase modulator, and you change the signal from being one
phase to being a different phase, there will be a dip in the amplitude during that
transition?
See ’816 Patent at 3:62–64 (“Light emitted from laser 12 is depolarized by a depolarizer 14 and
passes through a phase modulator 16, for example a Mach-Zender [sic, Mach-Zehnder] phase
modulator.”)
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A Yes.
Q Is there any way to avoid having a dip in the amplitude during the transition
from one phase to another when using a Mach-Zehnder modulator to phase
modulate a signal?
A It is unavoidable.
***
Q And the reason that you believe the amplitude is not constant is because of
transitory periods between bits, correct?
A Correct.
Q Now, the only evidence that you cite to in your report that the amplitude
fluctuates during transitions between bits is Dr. Dallesasse’s [(Plaintiff’s expert’s)]
statement that the amplitude of a PSK signal may fluctuate when transitioning
between bits, correct?
A That’s not the only source of my contention, it’s just my own knowledge of how
Mach-Zehnder modulators work. And there are also other issues that can come up
that would make, you know, possibly some rippling on the top of the signal as well
that could occur. In fact, Bill Thompson mentions that in his deposition too. But
fundamentally that’s the way Mach-Zehnders work is you will have that transitory
drop in signal between -- at least between adjacent 0 and 1 bits.
***
Q So would you agree that for a product that uses DPSK, the symbols that are
transmitted all have the same value for their amplitude?
[Objection]
A Ideally, yes.
***
Q Would you agree that in a DPSK product the amplitude of the signal is not used
to represent data?
[Objection]
A I would agree because the amplitude is constant. You could not tell from the
amplitude what symbol you have.
***
So would you agree that in the accused products that use QPSK, BPSK, or DPSK,
each bit of a transmission has a constant amplitude?
[Objection]
A What I mean here is that, again, ideally, each bit of a transmission would have - may have a constant amplitude, but the way in practice that this is done makes
that impossible using Mach-Zehnder modulators. Across a bit, there will be an
amplitude that varies with position in general.
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(Dkt. No. 365, Ex. OYS-ALU-B, Mar. 1, 2018 Buck dep. at 35:14–25, 180:6–25 & 183:23–
186:14.)
Defendants have submitted opinions of other experts purportedly to the contrary. (See Dkt.
No. 458, Ex. 6, Feb. 25, 2018 Brown Report, at ¶ 352 (“It has long been known that one need only
drive the two arms of the Mach-Zehnder with a common voltage in order for the phase modulation
in each leg to match, and thus for the Mach-Zehnder to function overall as a pure phase modulator,
altering phase in response to the drive voltage while maintaining amplitude constant.”); id. at ¶¶
353–55; id., Ex. 7, Papen Report, at ¶¶ 37–40; Dkt. No. 459, Ex. HW-4, Jan. 31, 2018 Willner
Report, at ¶¶ 59–60; Dkt. No. 268, Ex. COR-1, Kahn Report ¶¶ 167–70.
Yet, one of those experts, Dr. Jospeh Kahn, has opined that “a configuration that maintains
constant amplitude usually cannot achieve a signal quality sufficient for many telecommunications
applications.” (Id., at ¶ 170.) Plaintiff also submits that Dr. Kahn has testified as follows:
Q. . . . So is it your opinion that most and possibly all commercially available
optical telecommunications transponders use modulators that, by design, create a
signal that does not meet the court’s claim construction for phase modulate?
A. Yes.
Q. And does that include most and possibly all commercially available optical
telecommunications transponders that transmit using phase shift keying?
A. Yes.
Q. When you say most and possibly all commercially available optical
telecommunications transponders, are you aware of even a single commercially
available transponder that performs phase shift keying and satisfies the court’s
claim construction for phase modulate as you’ve applied that construction?
A. Yes. I’m just going to really mine my memory for a moment here.
I’m not aware of any.
(Dkt. No. 367, Ex. OYS-COR-B, Mar. 8, 2018 Kahn dep. at 134:5–24.)
On balance, to the extent these opinions are relevant to the present claim construction
dispute, the opinions cited by Plaintiff are more persuasive in the context of the patents-in-suit,
which claim improvements in telecommunications. See, e.g., ’816 Patent at Abstract; Kaneka
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Corp. v. Xiamen Kingdomway Grp. Co., 790 F.3d 1298, 1304 (Fed. Cir. 2015) (“A construction
that excludes all disclosed embodiments . . . is especially disfavored.”). This understanding is also
consistent with a specification disclosure regarding measuring “average” optical power. ’327
Patent at 5:35–37 (“average voltage level which represents the average optical power measured by
photodetector 153”). Plaintiff persuasively argues that “[t]here is no reason to average the optical
power of a signal with an amplitude that is supposed to be everywhere and at all times constant.”
(Dkt. No. 496, at 7.)
Finally, to whatever extent Defendants are arguing that the accused instrumentalities
cannot infringe because they could be configured so as to involve changes in amplitude that would
undermine the objectives set forth in the patents-in-suit, infringement is “not avoided merely
because a non-infringing mode of operation is possible.” VirnetX, Inc. v. Cisco Sys., Inc., 767 F.3d
1308, 1321–22 (Fed. Cir. 2014) (emphasis added) (quoting z4 Techs., Inc. v. Microsoft Corp., 507
F.3d 1340, 1350 (Fed. Cir. 2007)).
As to the doctrine of equivalents, Defendants have presented arguments as to sufficiency
of Plaintiff’s evidence and “vitiation,” as well as that “the patentee expressly disavowed in the
specification the very scope that Oyster is now attempting to capture with DOE.” (Dkt. No. 262,
at 13–15). These arguments are based on Defendants’ interpretation of the construction of “phase
modulate.” Given that the Court has rejected Defendants’ interpretation and is herein clarifying
the Court’s construction, the Court denies Defendants’ motion as to the doctrine of equivalents.
Based on all of the foregoing, the Court DENIES Defendants’ motion for partial summary
judgment and CLARIFIES the Court’s construction of “phase modulate” as set forth above.

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V. CONCLUSION
Defendants’ Motion for Partial Summary Judgment of Noninfringement Based on the
Absence of “Phase Modulation” (Dkt. No. 262) is hereby DENIED.
Further, for the reasons set forth above, the Court hereby CLARIFIES its construction of
“phase modulate” as follows: “alter the phase of light to create an optical signal having a
phase that is representative of data. Use of phase modulation excludes use of amplitude
modulation.”

So Ordered this
Jun 21, 2018

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