     NOTE: This disposition is nonprecedential.


 United States Court of Appeals
     for the Federal Circuit
              ______________________

 FIBER, LLC, A WYOMING LIMITED LIABILITY
                  COMPANY,
               Plaintiff-Appellant

                         v.

    CIENA CORPORATION, A DELAWARE
CORPORATION, CIENA COMMUNICATIONS, INC.,
   A DELAWARE CORPORATION, FINISAR
 CORPORATION, A DELAWARE CORPORATION,
            Defendants-Appellees

--------------------------------------------

 FIBER, LLC, A WYOMING LIMITED LIABILITY
                  COMPANY,
               Plaintiff-Appellant

                         v.

  VIAVI SOLUTIONS INC., FKA JDS UNIPHASE
 CORPORATION, LUMENTUM HOLDINGS, INC.,
 LUMENTUM INC., LUMENTUM OPERATIONS,
                    LLC,
             Defendants-Appellees

--------------------------------------------

 FIBER, LLC, A WYOMING LIMITED LIABILITY
                 COMPANY,
2                          FIBER, LLC v. CIENA CORPORATION




                   Plaintiff-Appellant

                           v.

      NOKIA OF AMERICA CORPORATION, FKA
       ALCATEL-LUCENT USA, INC., FINISAR
    CORPORATION, A DELAWARE CORPORATION,
                Defendants-Appellees
               ______________________

                      2019-1005
                ______________________

    Appeal from the United States District Court for the
District of Colorado in Nos. 1:13-cv-00840-PAB-KLM, 1:15-
cv-01743-PAB-KLM, 1:15-cv-02135-PAB-KLM, Judge
Philip A. Brimmer.
                  ______________________

              Decided: November 21, 2019
                ______________________

    GEORGE GUY MATAVA, Lewis Brisbois Bisgaard &
Smith, Denver, CO, argued for plaintiff-appellant. Also
represented by ALYSSA SANDROWITZ.

    JOEL SAYRES, Faegre Baker Daniels LLP, Denver, CO,
argued for all defendants-appellees. Defendants-appellees
Ciena Corporation, Ciena Communications, Inc., VIAVI
Solutions Inc., Lumentum Holdings, Inc., Lumentum Inc.,
Lumentum Operations, LLC also represented by DAVID
J.F. GROSS, JULIE WAHLSTRAND, Minneapolis, MN.

    DAVID C. RADULESCU, Radulescu LLP, New York, NY,
for defendant-appellee Finisar Corporation. Also repre-
sented by DANIEL KESACK, ETAI LAHAV.

     DAVID A. NELSON, Quinn Emanuel Urquhart &
FIBER, LLC v. CIENA CORPORATION                           3



Sullivan LLP, Chicago, IL, for defendant-appellee Nokia of
America Corporation.     Also represented by ZACHARY
CLARK, NATHAN HAMSTRA, MARC L. KAPLAN; ALLISON H.
ALTERSOHN, TIMOTHY CAINE, King & Spalding LLP, New
York, NY.
                ______________________

   Before PROST, Chief Judge, WALLACH and HUGHES,
                    Circuit Judges.
PROST, Chief Judge.
    Fiber, LLC (“Fiber”) appeals from a stipulated judg-
ment of invalidity and noninfringement entered by the
United States District Court for the District of Colorado in
favor of Ciena Corporation, Ciena Communications, Inc.,
Finisar Corporation, Viavi Solutions Inc., f/k/a JDS Uni-
phase Corporation, Lumentum Holdings, Inc., Lumentum
Inc., Lumentum Operations, LLC, and Nokia of America
Corporation, f/k/a Alcatel-Lucent USA, Inc. (collectively,
“Appellees”), following claim construction of U.S. Patent
No. 7,095,917 (“the ’917 patent”). For the reasons ex-
plained below, we affirm.
                             I
                             A
    The ’917 patent relates generally to an optical beam
switching system and specifically to “a plurality of optical
switch units (15, 17), each of which includes a mirror (29),
moveable in two axes, for purpose of switching light beams
from one optical fiber to another.” ’917 patent at Abstract.
Figure 2 of the ’917 patent, reproduced below, is a sche-
matic view of an optical switching unit 15:
4                            FIBER, LLC v. CIENA CORPORATION




Id. at fig.2, col. 4 ll. 16–17. The specification explains that
an optical beam light source, such as cable/fiber 17, trans-
mits light beam 13 toward mirror 25, which reflects the
beam in a different direction toward movable mirror 29,
which reflects the light toward an optical receptor, such as
another fiber. See id. at col. 4 ll. 14–17, col. 5 ll. 4–8, 19–
26.
    Independent claims 27 and 53 are relevant to this ap-
peal. Claim 27 recites:
    27. An optical beam switching system for transmit-
    ting an optical beam from at least one source to at
    least one of a plurality of optical receptors compris-
    ing:
    at least one source of an optical beam;
    at least one first beam directing device mounted
    across a first area of free space from the source;
    at least one additional beam directing device;
    at least one second beam directing device mounted
    across a second area of free space from the first
    beam directing device;
FIBER, LLC v. CIENA CORPORATION                             5



   a plurality of optical receptors;
   a control operative for at least one of 1) positioning
   a first beam directing device to direct the optical
   beam from at least one source to at least one addi-
   tional beam directing device, 2) positioning at least
   one additional beam directing device to direct the
   optical beam from said additional beam directing
   device to a second beam directing device, and 3) po-
   sitioning a second beam directing device to direct
   the optical beam from said second beam directing
   device to a selected one of said plurality of optical
   receptors; and
   at least one data gathering and transmission ele-
   ment to provide an indication regarding the current
   orientation of the controlled beam directing device
   or the current location of the optical beam to the
   control for adjusting at least one of the beam direct-
   ing devices.
Id. at claim 27 (emphases added).
   Claim 53 recites:
   53. An optical beam switching system for transmit-
   ting an optical beam from at least one source to at
   least one of a plurality of optical receptors compris-
   ing:
   at least one source of an optical beam;
   at least one first beam directing device mounted
   across a first area of free space from the source;
   a plurality of optical receptors mounted across a
   second area of free space from the first beam direct-
   ing device;
   a control so that a first beam directing device will
   be positioned to direct the optical beam from at
6                            FIBER, LLC v. CIENA CORPORATION




    least one source to a selected one of said plurality
    of optical receptors; and
    at least one data gathering and transmission ele-
    ment to provide an indication regarding the current
    orientation of the controlled beam directing device
    or the current location of the optical beam to the
    control for adjusting at least one of the beam direct-
    ing devices.
Id. at claim 53 (emphases added).
                              B
    In 2013, Fiber filed suit against Ciena Communica-
tions, Inc. and Ciena Corporation alleging infringement of
the ’917 patent and a related patent (“the Ciena case”). The
Ciena case was stayed pending IPR for over two years and
reopened in November 2015. In 2015, Fiber filed suit
against Viavi Solutions Inc., f/k/a JDS Uniphase Corpora-
tion, Lumentum Holdings, Inc., Lumentum Inc., and Lu-
mentum Operations, LLC (“the Lumentum case”), and
separately against Nokia of America Corporation, f/k/a Al-
catel-Lucent USA, Inc. (“the Alcatel case”), asserting the
same patents. In 2016, Finisar Corporation joined as an
intervenor defendant in the Ciena case and the Alcatel
case. In 2016, the district court consolidated the three
cases.
    The district court held a claim construction hearing on
December 2, 2016 and issued its claim construction order
on September 6, 2017. Fiber, LLC v. Ciena Corp., No. 13-
CV-00840-PAB-KLM, 2017 WL 3896443 (D. Colo. Sept. 6,
2017). The construction of three terms—“control,” “data
gathering and transmission element,” and “positioning”—
are at issue in this appeal.
    The district court held that the term “control,” as used
in claims 27 and 53, is a means-plus-function limitation,
FIBER, LLC v. CIENA CORPORATION                             7



invoking § 112, ¶ 6. 1 Id. at *13–14. The district court be-
gan by acknowledging that because the claims do not use
the word “means,” there is a rebuttable presumption that
§ 112, ¶ 6 does not apply. See id. But, as the district court
noted, “the presumption can be overcome and § 112, para. 6
will apply if the challenger demonstrates that the claim
term fails to ‘recite sufficiently definite structure’ or else
recites ‘function without reciting sufficient structure for
performing that function.’” Williamson v. Citrix Online,
LLC, 792 F.3d 1339, 1349 (Fed. Cir. 2015) (quoting Watts
v. XL Sys., Inc., 232 F.3d 877, 880 (Fed. Cir. 2000)). The
district court found that the term “control” is used in the
claims of the ’917 patent in relation to a function: position-
ing a beam directing device. Fiber, 2017 WL 3896443,
at *14. The district court also observed that “[i]n each in-
stance, the word control could be replaced by ‘means’ with-
out substantially changing the meaning of the claims.” Id.
The district court therefore found that the presumption
that § 112, ¶ 6 did not apply had been overcome in this case
because the “control” terms are “directly tied to a function”
of positioning the beam directing device and because “a
POSITA would not understand the term to describe the rel-
evant structure.” Id.
    Having found that the term “control” invokes § 112,
¶ 6, the district court then considered whether the specifi-
cation recited sufficient corresponding structure for per-
forming the function. Id. at *14–16. For structure, Fiber
identified a portion of the specification that incorporates
another patent, U.S. Patent No. 5,177,348 (“the ’348



    1    On September 16, 2012, when the Leahy-Smith
America Invents Act (AIA), Pub. L. No. 112–29, took effect,
35 U.S.C. § 112, ¶ 6 was replaced with newly designated
§ 112(f). Because the application resulting in the ’917 pa-
tent was filed before the effective date of the AIA, we refer
to the pre-AIA version of § 112.
8                           FIBER, LLC v. CIENA CORPORATION




patent”), by reference. The district court considered and
rejected this argument, stating that, “the reference to the
’348 [p]atent in the cited portion of the specification dis-
cusses data gathered related to mirror positioning which is
then sent to the control. It does not indicate structures of
the control.” Id. at *15. The district court considered Fi-
ber’s other arguments and held that the specification lacks
corresponding structure, rendering the term invalid as in-
definite. Id. at *14–16.
    The district court construed the term “data gathering
and transmission element” as a means-plus-function limi-
tation and held that the specification disclosed sufficient
corresponding structure, making it not indefinite. Id. at
*16–17. The district court construed the “positioning” lim-
itations to mean “changing the physical orientation of a
beam directing device.” Id. at *18.
    Following claim construction, the parties stipulated
that under the district court’s constructions, all of the as-
serted claims of the ’917 patent were invalid and none of
the accused products infringed. J.A. 9, 15, 21. The district
court entered final judgment of invalidity and noninfringe-
ment in favor of Appellees. J.A. 2, 4, 6.
    Fiber timely appealed, challenging the district court’s
construction of the terms “control,” “data gathering and
transmission element,” and “positioning.” We have juris-
diction pursuant to 28 U.S.C. § 1295(a)(1).
                             II
                             A
    We review the district court’s claim constructions de
novo, and any underlying factual findings based on extrin-
sic evidence for clear error. Teva Pharm. USA, Inc. v.
Sandoz, Inc., 135 S. Ct. 831, 841 (2015); TEK Glob., S.R.L.
v. Sealant Sys. Int’l, Inc., 920 F.3d 777, 785 (Fed. Cir.
2019). “[W]hen the district court reviews only evidence in-
trinsic to the patent (the patent claims and specifications,
FIBER, LLC v. CIENA CORPORATION                             9



along with the patent’s prosecution history), the judge’s de-
termination will amount solely to a determination of law,
and the Court of Appeals will review that construction de
novo.” Teva, 135 S. Ct. at 841.
    Whether a term is a means-plus-function limitation in-
voking § 112, ¶ 6 “is a legal question of claim construction
that we review de novo.” MTD Prods. Inc. v. Iancu, 933
F.3d 1336, 1341 (Fed. Cir. 2019). The use of the word
“means” in a claim element creates a rebuttable presump-
tion that § 112, ¶ 6 applies. Williamson, 792 F.3d at 1348.
Failure to use the word “means” creates a rebuttable pre-
sumption that § 112, ¶ 6 does not apply. Id. When a claim
term lacks the word “means,” the presumption that § 112,
¶ 6 does not apply can be overcome “if the challenger
demonstrates that the claim term fails to ‘recite sufficiently
definite structure’ or else recites ‘function without reciting
sufficient structure for performing that function.’” Id. at
1349 (quoting Watts, 232 F.3d at 880).
    “Construing a means-plus-function claim term is a two-
step process. The court must first identify the claimed
function. Then, the court must determine what structure,
if any, disclosed in the specification corresponds to the
claimed function.” Id. at 1351–52 (citation omitted). If the
patentee fails to disclose adequate structure corresponding
to the claimed function, the claim is indefinite. Id. The
ultimate conclusion that a claim is indefinite under 35
U.S.C. § 112, ¶ 2 is a legal conclusion, which we review de
novo. Cox Commc’ns, Inc. v. Sprint Commc’n Co. LP, 838
F.3d 1224, 1228 (Fed. Cir. 2016).
                              B
    We begin with the term “control.” As explained above,
the district court held that the term “control,” as used in
claims 27 and 53 of the ’917 patent, is a means-plus-func-
tion limitation and that the specification lacks correspond-
ing structure, rendering the term invalid as indefinite.
Fiber, 2017 WL 3896443, at *13–16. On appeal, Fiber
10                          FIBER, LLC v. CIENA CORPORATION




argues: (1) “control” is not a means-plus-function term and
does not invoke § 112, ¶ 6; and (2) even if “control” is a
means-plus-function term, it is not indefinite because the
specification discloses sufficient corresponding structure.
                             1
    We agree with the district court that “control” is a
means-plus-function limitation. The limitation does not in-
clude the word “means,” so there is a rebuttable presump-
tion that § 112, ¶ 6 does not apply. However, the
presumption has been overcome in this case. We agree
with the district court that the term “control,” which is
used in relation to the function of positioning the beam di-
recting device, is a means-plus-function term.
    On appeal, Fiber argues that a person of skill in the art
would interpret “control” to refer to sufficiently definite
structure based on intrinsic and extrinsic evidence. Begin-
ning with the intrinsic evidence, Fiber argues that “[t]here
is more than ample structure set forth in the specification
and prosecution history.” Appellant’s Br. 20. For example,
Fiber argues that the “control,” depicted in Figure 7A of the
’917 patent reproduced below, imparts structure.
FIBER, LLC v. CIENA CORPORATION                              11




Figure 7A is a cross-section of an optical switch package
including mirror 29 and the optic unit’s sensing control sys-
tem 100. ’917 patent at col. 4 ll. 38–41, col. 7 ll. 51–53. But,
as shown above, the “control” depicted in Figure 7A is a
generic box with no indication of any structure.
    We conclude, like the district court did, that the intrin-
sic evidence indicates that “control” is a means-plus-func-
tion limitation. 2




    2   Fiber also argues that extrinsic evidence further
supports its position that someone skilled in the art would
interpret “control” as structural. Appellant’s Br. 28–32.
But, as Fiber notes, the district court’s claim construction
relied only on intrinsic evidence. Because we agree with
the district court’s claim construction based on the intrinsic
12                            FIBER, LLC v. CIENA CORPORATION




     Finally, Fiber makes several arguments that the dis-
trict court committed legal error in its construction of the
term “control.” Appellant’s Br. 32–37. Fiber argues that
the district court “failed to give effect to the rebuttable pre-
sumption against means-plus-function.” Id. at 32–34. We
disagree. The district court acknowledged that the claims
did not recite the words “means,” properly applied the pre-
sumption against means-plus-function treatment, and
found that the presumption had been overcome. Fiber,
2017 WL 3896443, at *13–14. Fiber then argues that “con-
trol” is more similar to “circuit,” which it argues inherently
connotes structure, than it is to “control means,” which it
acknowledges does not typically connote structure. Appel-
lant’s Br. 34–36. But Fiber does not convincingly explain
why “control” is more analogous to “circuit” than to “control
means,” and we see no reason why it would be in this cir-
cumstance.
    For these reasons, we conclude that with respect to the
“control” limitation, the presumption against means-plus-
function claiming has been overcome. We therefore agree
with the district court that this limitation is subject to the
provisions of § 112, ¶ 6.
                               2
     Having determined that “control” is subject to § 112,
¶ 6, we now turn to whether the specification discloses suf-
ficient structure that corresponds to the claimed function
of positioning a beam directing device to direct the optical
beam. We agree with the district court that the specifica-
tion of the ’917 patent does not disclose any corresponding
structure for the function of the claimed “control,” and that
claims 27 and 53 are therefore indefinite.




evidence alone, we do not reach the extrinsic evidence in
the first instance on appeal.
FIBER, LLC v. CIENA CORPORATION                            13



     On appeal, Fiber fails to identify a structure in the
’917 patent corresponding to the function. Fiber argues
that the ’348 patent incorporated by reference in the spec-
ification provides sufficient corresponding structure. Ap-
pellant’s Br. 39. 3      As an initial matter, “material
incorporated by reference cannot provide the correspond-
ing structure necessary to satisfy the definiteness require-
ment for a means-plus-function clause.” Default Proof
Credit Card Sys., Inc. v. Home Depot U.S.A., Inc., 412 F.3d
1291, 1301 (Fed. Cir. 2005). Even if incorporating corre-
sponding structure by reference was permissible, we agree
with the district court that the ’348 patent does not impart
structure for the “control.” See Fiber, 2017 WL 3896443,
at *15.
    Relying on expert testimony, Fiber argues that “a
POSITA would have understood ‘control’ to refer to cir-
cuitry and a drive mechanism.” Appellant’s Br. 40. How-
ever, the definiteness requirement is that the specification
adequately disclose corresponding structure. Expert testi-
mony cannot create structure where none is adequately
disclosed in the specification. Williamson, 792 F.3d at 1354
(“The testimony of one of ordinary skill in the art cannot
supplant the total absence of structure from the specifica-
tion.”).
    We therefore affirm the district court’s construction
that “control” is a means-plus-function limitation invoking
§ 112, ¶ 6 and that there is insufficient corresponding
structure in the specification, rendering the claim invalid
as indefinite. We accordingly affirm the district court’s


    3   In its briefing, Fiber also argues that the ’348 pa-
tent recites structure for the term “control” such that § 112,
¶ 6 is not invoked. Appellant’s Br. 23–25. We disagree.
The ’348 patent does not provide structural significance to
the term “control” in this case. See Williamson, 792 F.3d
at 1351; see also Fiber, 2017 WL 3896443, at *15.
14                          FIBER, LLC v. CIENA CORPORATION




final judgment that the term “control” renders all of the as-
serted claims of the ’917 patent invalid as indefinite under
§ 112, ¶ 2.
                             C
    Our holding on the “control” limitations described
above is sufficient to resolve this appeal. The parties
agreed that if we affirmed the district court’s holding that
“control” was a means-plus-function limitation and that it
was invalid as indefinite, all of the asserted claims of the
’917 patent would be invalid and the entire case would be
resolved. See Oral Argument at 3:57–4:15 (Fiber), 12:01–
12:23 (Appellees), Fiber, LLC v. Ciena Corp. (No. 2019-
1005), http://www.cafc.uscourts.gov/oral-argument-record-
ings. Because we agree that the district court correctly con-
strued “control” and found it invalid as indefinite, we do
not reach the district court’s construction of the terms
“data gathering and transmission element” and “position-
ing.”
                             III
    We have considered Fiber’s remaining arguments and
find them unpersuasive. We affirm the district court’s final
judgment that all of the asserted claims of the ’917 patent
are invalid as indefinite.
                       AFFIRMED
