       NOTE: This disposition is nonprecedential.


  United States Court of Appeals
      for the Federal Circuit
                ______________________

          OTTO BOCK HEALTHCARE LP,
                Plaintiff-Appellant,

                           v.

     ÖSSUR HF AND ÖSSUR AMERICAS, INC.,
             Defendants-Appellees.
            ______________________

                      2013-1650
                ______________________

   Appeal from the United States District Court for the
Central District of California in No. 13-CV-0891, Judge
Cormac J. Carney.
                 ______________________

              Decided: February 18, 2014
               ______________________

     BRIAN R. MATSUI, Morrison & Foerster, LLP, of Wash-
ington, DC, argued for plaintiff-appellant. With him on
the brief was DEANNE E. MAYNARD. Of counsel on the
brief was CHARLES S. BARQUIST, of Los Angeles, Califor-
nia.

   BRENTON R. BABCOCK, Knobbe, Martens, Olson &
Bear, LLP, of Irvine, California, argued for defendants-
appellees. With him on the brief was NICHOLAS M.
ZOVKO.
2                      OTTO BOCK HEALTHCARE LP   v. OSSUR HF



                  ______________________

    Before LOURIE, DYK, and WALLACH, Circuit Judges.
LOURIE, Circuit Judge.
    Otto Bock HealthCare LP (“Otto Bock”) appeals from
the decision of United States District Court for the Cen-
tral District of California denying a motion for a prelimi-
nary injunction against Össur HF and Össur Americas,
Inc. (“Össur”) because Otto Bock is unlikely to succeed on
the merits of its infringement claim.           Otto Bock
HealthCare LP v. Össur HF and Össur Ams., Inc., No. 13-
CV-00891, 2013 WL 4828791 (C.D. Cal. Aug. 22, 2013).
Because the district court did not abuse its discretion in
view of the construed claim terms, we affirm.
                       BACKGROUND
     Otto Bock owns U.S. Patent 6,726,726 (the “’726 pa-
tent”), which is directed to an apparatus and method for
managing residual limb volume in an artificial limb. ’726
patent col. 1 ll. 15–18. The claimed invention prevents
volume loss in the amputee’s residual limb that results
from weight-bearing forces placed on that limb. Id. The
’726 patent describes a vacuum socket for amputees that
incorporates, inter alia, a liner, a single socket, and a
vacuum source to draw the residual limb into firm and
total contact with the socket. Id. col. 4 ll. 39–60. The ’726
patent further incorporates by reference U.S. Patent
Application 09/534,274 (the “’274 application”), which
discloses a combination multi-chamber piston/cylinder
pump and shock absorber to maintain the vacuum. Id.
col. 13 ll. 7–8.
    Claim 1 is exemplary and reads as follows:
        1. In an artificial limb for amputees who
    have a residual limb, an apparatus for managing
    residual limb volume, wherein application of a
    vacuum prevents loss of residual limb volume due
OTTO BOCK HEALTHCARE LP   v. OSSUR HF                       3



   to weight-bearing pressures and locks the residual
   limb to the artificial limb without causing swell-
   ing of the residual limb, the apparatus compris-
   ing:
   (a) a flexible liner having a cavity with a volume
       less than that of the residual limb, whereby the
       liner is tensioned into a total contact relation-
       ship with the residual limb;
   (b) a single socket with a volume and shape to re-
       ceive a substantial portion of the residual limb
       and the liner, the socket having a cavity
       adapted to receive the residual limb and the
       liner;
   (c) a vacuum source connected to the socket cavity
       between the liner and the socket, wherein ap-
       plication of the vacuum source to the socket
       cavity draws the residual limb and liner into
       firm and total contact with the socket, thereby
       locking the residual limb to the socket without
       causing swelling of the residual limb into the
       socket;
   (d) a seal means for sealing the socket cavity;
   (e) a means to maintain a vacuum in the socket
       cavity, in the presence of some air leakage past
       the seal means; and
   (f) further comprising a thin sheath between the
       liner and the socket, to assist the even distribu-
       tion of vacuum in the cavity about the liner;
   wherein application of the vacuum source of the
     socket cavity prevents the loss of residual limb
     volume due to weight-bearing pressures.
’726 patent col. 14 ll. 35–65 (emphases added). Claims 6,
9, 15, and 18, which are dependent, also require a “seal
means” and a “means to maintain a vacuum.” Id. col. 15 l.
4                     OTTO BOCK HEALTHCARE LP   v. OSSUR HF



9–col. 16 l. 8. Those claim limitations are crucial to this
appeal.
     Claims 1 and 10 recite a “seal means for sealing the
socket cavity,” and claims 1 and 11 recite a “means to
maintain [a] vacuum in the [socket] cavity. ’726 patent
col. 14 l. 55–col. 15 l. 50. Claims 6 and 18 depend from
Claims 1 and 10, respectively, and further limit the “seal
means” to an “annular seal.” Id. col. 15 l. 9–col. 16 l. 17.
Claims 9 and 15 depend from claims 1 and 11, respective-
ly, and further limit the “means to maintain a vacuum” to
a “weight-actuated vacuum pump.” Id. col. 15 l. 20–col.
16 l. 7.
    Össur makes mechanical vacuum pump prosthetic
products, including the Iceross Seal-In® V liner and
UnityTM vacuum suspension module. Otto Bock, 2013 WL
4828791 at *2. The Iceross Seal-In® V liner compensates
for the volume fluctuations and shape changes of an
amputee’s residual limb by expanding and exerting pres-
sure against the interior socket wall. A “dual-seal” mech-
anism prevents the outer surface of the Iceross Seal-In® V
liner from fully contacting the sockets, resulting in vary-
ing levels of pressure from the liner against the socket.
Össur’s UnityTM module uses a heel-actuated membrane
to create a vacuum. The UnityTM module in combination
with the Iceross Seal-In® V liner can be used to create an
artificial limb for amputees.
     Otto Bock sued Össur for infringement of claims 6, 9,
15, and 18 of the ’726 patent by importing, selling, and
offering for sale and use in the United States the follow-
ing combination of Össur products: (1) the Iceross Seal-
In® V liner; (2) the Re-Flex Rotate Foot or Re-Flex Shock;
and (3) the UnityTM vacuum pump module and valve
(collectively the “Accused Products”). Id. at *2. Otto Bock
moved for a preliminary injunction. Id. at *1.
    The district court construed the two means-plus-
function claim limitations pursuant to 35 U.S.C. § 112, ¶ 6
OTTO BOCK HEALTHCARE LP   v. OSSUR HF                    5



and found that Otto Bock was unlikely to succeed on the
merits of its infringement claim. * Id. at *3–6. Agreeing
with Otto Bock’s expert Dr. Gard, the court construed
“seal means” as an annular seal with a narrow ring
around the liner that has a rectangular cross-section. Id.
The court then concluded that Otto Bock failed to clearly
show that Össur’s Seal-In® V liner’s membrane seal
performed the sealing function in substantially the same
way as the annular seal disclosed in the ’726 patent. Id.
at *4.
    Next, the district court construed “means to maintain
a vacuum.” Id. The court noted that the “weight-
actuated vacuum pump” limitation in claims 9 and 15
might cover an indefinite number of structures, but found
that the term should be informed by the written descrip-
tion’s disclosure that a vacuum-maintaining means may
take the form of a “weight-actuated vacuum pump as
disclosed in [the ’274 application].” Id. at *5. The court
then concluded that Össur’s UnityTM module and the
weight-actuated vacuum pump as disclosed in the ’274
application were neither structurally identical nor equiva-
lent. Id. at *5–6.
    Accordingly, the district court found that Otto Bock
was unlikely to prevail in showing that Össur’s accused
products satisfied the “seal means” limitation in claims 6,
9, 15, and 18 and the “means to maintain a vacuum”
limitation in claims 6, 9, and 15 because Össur’s products
used a different seal means and did not use a pis-
ton/cylinder pump as a means to maintain a vacuum. Id.


   *    Paragraph 6 of 35 U.S.C. § 112 was replaced with
newly designated § 112(f) when § 4(c) of the Leahy-Smith
America Invents Act (“AIA”), Pub. L. No. 112-29, took
effect on September 16, 2012. Because this case was filed
before that date, we will refer to the pre-AIA version of
§ 112.
6                      OTTO BOCK HEALTHCARE LP     v. OSSUR HF



at *6. The court thus denied Otto Bock’s motion for a
preliminary injunction. Id.
   Otto Bock appealed. We have jurisdiction pursuant to
28 U.S.C. § 1295(a)(1).
                         DISCUSSION
    We review a grant or denial of a preliminary injunc-
tion for abuse of discretion.        Amazon.com, Inc. v.
Barnesandnoble.com, Inc., 239 F.3d 1343, 1350 (Fed. Cir.
2001). An abuse of discretion is only established if “the
court made a clear error of judgment in weighing relevant
factors or exercised its discretion based upon an error of
law or clearly erroneous factual findings.”        Sanofi-
Synthelabo v. Apotex, Inc., 470 F.3d 1368, 1374 (Fed. Cir.
2006). We address claim construction as a matter of law,
which we review without deference. See Cybor Corp. v.
FAS Techs., Inc., 138 F.3d 1448, 1456 (Fed. Cir. 1998) (en
banc).
     The district court’s denial of a preliminary injunction
as unlikely to succeed on the merits was premised in part
on its interpretation of the limitations “seal means” and
“means for maintaining a vacuum” as claimed in Otto
Bock’s ’726 patent. To construe a claim limitation, the
trial court must determine the meaning of any disputed
words from the perspective of one of ordinary skill in the
pertinent art at the time of filing. Phillips v. AWH Corp.,
415 F.3d 1303, 1313 (Fed. Cir. 2005) (en banc). Although
it is unacceptable to import limitations into a claim from
the written description, “the specification ‘is always
highly relevant to the claim construction analysis. Usual-
ly, it is dispositive; it is the single best guide to the mean-
ing of a disputed term.’” Id. at 1315 (quoting Vitronics
Corp. v. Conceptronic, Inc., 90 F.3d 1576, 1582 (Fed. Cir.
1996)).
    In order to establish infringement of a means-plus-
function term, a patentee must show that “the relevant
OTTO BOCK HEALTHCARE LP    v. OSSUR HF                      7



structure in the accused device perform[s] the identical
function recited in the claim and [is] identical or equiva-
lent to the corresponding structure in the specification.”
Odetics, Inc. v. Storage Technology Corp., 185 F.3d 1259,
1267 (Fed. Cir. 1999) (citations omitted).
                      I. Seal Means
    Otto Bock argues that the term “seal means” in claims
6, 9, 15, and 18 of the ’726 patent is defined broadly in the
dependent claims and the written description as “an
annular seal between the liner and the socket.” Össur
responds that the patent expressly links “a narrow ring
with a rectangular cross section” to the function of “seal-
ing the socket activity,” a more narrow interpretation.
    We agree with Össur that the ’726 patent expressly
links two structures, namely, the polyurethane sleeve and
an annular seal, to the function of “sealing the socket
cavity.” ’726 patent col. 6 ll. 49–54; col. 12 ll. 55–58; col.
13 ll. 24–41. No other structures are described in the
written description for performing the sealing function.
Our focus, therefore, is on the construction of “annular
seal.”
    The ’726 patent depicts an “annular seal” as a narrow
ring with a rectangular cross-section around the liner in
figures 17, 18, and 20. “The annular seal . . . is adapted to
sealingly engage the suspension sleeve 86, producing a
seal against the vacuum in cavity 62 at the point of con-
tact with the suspension sleeve 86.” Id. col. 13 ll. 27–31.
In another embodiment, “the annular seal 140 does not
make contact with the suspension sleeve 86, but rather
makes contact with the inner wall 63 of the socket 60, and
makes a seal at that point.” Id. col. 13 ll. 35–38. These
two passages, in combination with figures 17, 18, and 20,
make clear that the “annular seal” is properly construed
as a narrow ring with a rectangular cross-section.
8                      OTTO BOCK HEALTHCARE LP   v. OSSUR HF



    Although dependent claims 6 and 18 recite “wherein
the seal means further comprises an annular seal be-
tween the liner and the socket,” those claims do not stand
alone. Phillips, 415 F.3d at 1315. The claims must be
interpreted in light of the written description, which
requires a more narrow interpretation of the term “annu-
lar seal.” The district court thus did not err in construing
the term “means for sealing” to mean a narrow ring
around the liner that has a rectangular cross-section.
    Össur’s Seal-In® V liner does perform the function of
sealing the socket cavity; however, the disclosed annular
seal in the ’726 patent and the Seal-In® V liner are not
structurally identical to the “seal means” as disclosed.
The Seal-In® V liner’s membrane seal is not structurally
identical to the annular seal disclosed in the ’726 patent
because, unlike in the patent, the membrane seal (1) has
a wide band of contact with the socket; (2) has two narrow
seal rings on the exterior surface; (3) has pliable blades on
the interior surface; (4) has chamfered edges; and (5) is
bonded to a recess in the liner.
     The Seal-In® V liner’s membrane is also not structur-
ally equivalent to the annular seal disclosed in the ’726
patent. First, the membrane seal’s “dual-sealing mecha-
nism” performs the sealing function in a substantially
different manner from the smooth-surface annular seal
disclosed in the patent. Össur’s membrane seal does not
completely press against the socket’s interior wall; rather,
the two outer seal rings press against the interior wall of
the socket. Otto Bock, 2013 WL 4828791 at *3. According
to Otto Bock’s expert, Dr. Gard, other portions of the
membrane seal’s wide surface, however, “may not press
against the socket, and further may not touch the socket
wall at all.” Id. Second, the interior blades cause the
Seal-In® V liner’s membrane seal to perform the sealing
function differently. Dr. Gard found that “when a force is
exerted to pull the liner out of a socket, the blades expand
outwardly, which in turn creates extra pressure of the
OTTO BOCK HEALTHCARE LP   v. OSSUR HF                     9



seal wall against the socket wall, thereby making it more
difficult to lose suspension of the liner.” Id. The district
court thus did not clearly err in finding that the Seal-In®
V liner’s membrane seal does not perform the sealing
function in substantially the same way as the annular
seal disclosed in the ’726 patent.
           II. Means to Maintain a Vacuum
    Otto Bock argues that the term “means to maintain a
vacuum” in claims 6, 9, and 15 of the ’726 patent is de-
fined in the dependent claims and the written description
as “a weight-actuated vacuum pump” and that the claims
therefore encompass all weight-actuated vacuum pumps.
Otto Bock also asserts that Atmel Corp. v. Info Storage
Devices, 198 F.3d 1374 (Fed. Cir. 1999), forecloses the use
of a patent application incorporated by reference to add
structure to a means-plus-function claim. Appellant Br.
31–32. Össur responds that the only structure described
in the written description of the patent is “a weight actu-
ated vacuum pump and shock absorber as disclosed in
[the ’274 application].”
    We agree with Össur. The parties do not dispute that
the key structure at issue is the “weight-actuated vacuum
pump” as claimed in claims 9 and 15 and as further
disclosed in the specification in combination with an
incorporation by reference to the ’274 application. Id. at
*4. Although it is true that claims 9 and 15 do not refer to
the ’274 application, “[those] claims, of course, do not
stand alone.” Phillips, 415 F.3d at 1315. The only refer-
ence in the specification to the term states: “To maintain
the vacuum in the cavity, either a regulator means 80, a
vacuum reservoir 110, or a weight-actuated vacuum pump
and shock absorber as disclosed in [the ’274 application],
may be employed.” ’726 patent col. 13 ll. 5–8 (emphasis
added). And all of the claims must be interpreted in light
of the written description, which requires an interpreta-
tion that includes the ’274 application.
10                    OTTO BOCK HEALTHCARE LP   v. OSSUR HF



    Further, Otto Bock’s reliance on Atmel is misplaced.
Atmel only foreclosed the use of the content of a nonpa-
tent publication incorporated by reference to add struc-
ture to a means-plus-function claim. Atmel, 198 F.3d at
1382. Atmel did not purport to include U.S. patent appli-
cations. In fact, 37 C.F.R. 1.57(d) specifically envisions
using a U.S. patent application incorporated by reference
to define structure for the purpose of 35 U.S.C. § 112, ¶ 6.
The court thus did not err in using the ’274 application’s
incorporation by reference to construe the term “means
for maintaining a vacuum” to mean a “weight-actuated
vacuum pump as disclosed in [the ’274 application].”
     In view of this claim construction, we further agree
with the analysis of the district court that the structures
of Össur’s UnityTM module and the weight-actuated
vacuum pump as disclosed in the ’274 application are
neither identical nor equivalent. The structures are not
identical because the vacuum pump disclosed in the ’274
application has a piston/cylinder module that is integrat-
ed into the pylon of the prosthetic limb, ’274 application
col. 7 ll. 5–17, whereas the UnityTM module attaches to
the foot module and has no piston and no preexisting air
chamber. Otto Bock, 2013 WL 4828791 at *5.
    The two structures are not equivalent because they
maintain the vacuum in different ways. The pump dis-
closed in the ’274 application draws air out of the socket
cavity by using the amputee’s body weight to force a
piston downward within a cylinder against a chamber of
compressed air. Id. col. 14 ll. 55–col. 15 l. 4. The UnityTM
module, in contrast, draws air from the socket cavity by
using heel pressure to pull apart two blades located on the
foot module, thereby deforming an elastic membrane that
has zero, or near-zero, air chamber volume in its unde-
formed state. Otto Bock, 2013 WL 4828791 at *5. The
district court thus did not clearly err in finding that the
structure of the UnityTM module was not identical or
OTTO BOCK HEALTHCARE LP   v. OSSUR HF                   11



equivalent to the structure of the weight-actuated vacuum
pump disclosed in the ’274 application.
                       CONCLUSION
    Because the Accused Products do not satisfy either
the “seal means” or “means to maintain a vacuum” limita-
tions of the ’726 patent as properly construed, Otto Bock
is unlikely to establish infringement of asserted claims 6,
9, 15, and 18. We therefore conclude that the district
court did not abuse its discretion in denying preliminary
injunctive relief. Thus, the decision of the district court
denying the motion for a preliminary injunction is af-
firmed.
                      AFFIRMED
