NMT MEDICAL, INC. and CHILDREN’S MEDICAL CENTER CORPORATION v. Cardia, Inc.

Note: This disposition is nonprecedential.
United States Court of Appeals for the Federal Circuit
2006-1645
NMT MEDICAL, INC.
and CHILDREN’S MEDICAL CENTER CORPORATION,
Plaintiffs-Appellants,
v.
CARDIA, INC.,
Defendant-Appellee.
Douglas J. Kline, Goodwin Procter LLP, of Boston, Massachusetts, argued for
plaintiffs-appellants. With him on the brief were William A. Meunier, Kenneth E.
Radcliffe, and Michael G. Strapp.
David A. Allgeyer, Lindquist & Vennum P.L.L.P., of Minneapolis, Minnesota,
argued for defendant-appellee. With him on the brief was Christopher R. Sullivan.
Appealed from: United States District Court for the District of Minnesota
Judge Joan N. Ericksen

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NOTE: This disposition is nonprecedential.
United States Court of Appeals for the Federal Circuit
2006-1645
NMT MEDICAL, INC.
and CHILDREN’S MEDICAL CENTER CORPORATION,
Plaintiffs-Appellants,
v.
CARDIA, INC.,
Defendant-Appellee.
__________________________
DECIDED: June 6, 2007
__________________________
Before MICHEL, Chief Judge, MAYER and GAJARSA, Circuit Judges.
GAJARSA, Circuit Judge.
This is a patent infringement case. Plaintiffs NMT Medical, Inc. and Children’s
Medical Center Corporation (collectively “NMT”) are the assignees of U.S. Patent No.
5,451,235 (“the ’235 patent”). The United States District Court for the District of
Minnesota granted summary judgment to defendant Cardia, Inc. (“Cardia”) that its
accused heart defect repair device did not infringe any of the asserted claims of the ’235
patent. NMT appeals the judgment to this court. Because the district court erred by
finding no triable issues of fact as to asserted claims 1-5 and by erroneously construing
asserted claim 12, we vacate the summary judgment order and remand for further
proceedings.

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I. BACKGROUND
A. Technology and patent
This case involves implanted medical devices used to repair heart defects which
take the form of holes in the cardiac tissue. One such defect, known as “patent foramen
ovale,” is a congenital flaw in which a small hole between the left and right atria of the
heart fails to close following birth. Surgeons apply the devices at issue to correct this
flaw using a catheter, thus avoiding open-heart surgery. The patented device consists
of two connected “occluders,” flanges that are collapsed inside the catheter but which
spring open like an umbrella to a size larger than the defect once the surgeon removes
the catheter. To correct the defect, the catheter is inserted into the body via an artery or
vein and moved so that it protrudes through the hole to be patched. One occluder is
then allowed to open on each side of the defective heart wall, blocking the undesired
passage of blood and fixing the device in place. Figure 8c of the ’235 patent illustrates
the insertion process:
In the figure, the device has been delivered by catheter 190 into a hole in the cardiac
tissue. Occluder 12 is open and blocking blood flow on the right side of the hole, and
when the catheter is removed, occluder 14 will spring open on the left side.
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NMT asserts infringement of six claims of the ’235 patent: Claims 1-5 and Claim
12. Claims 1 and 12 are independent claims, while claims 2 to 5 are dependent on
Claim 1. Claim 1 reads as follows:
A device for percutaneous transluminal repair of septal defects
comprising:
a) a first occluder having an initial cross sectional configuration smaller
than that of the defect to be repaired and a second expanded
configuration larger than that of the detect;
b) a second occluder having an initial cross sectional configuration smaller
than that of the detect to be repaired and a second expanded
configuration larger than that of the defect; and
c) said first occluder and said second occluder being connected by a
connector means for fastening the first occluder to the second occluder
said connector means comprising a pivot means for allowing rotation of
the first occluder relative to the second occluder when said occluders are
in the expanded configuration.
’235 patent col.10 ll.43-59 (emphasis added). Claims 2-5 depend from Claim 1, adding
limitations not at issue here. Claim 12 differs from Claim 1 only in its part (c), which
reads:
c) said first occluder and said second occluder being connected by a
connector means for fastening the first occluder to the second occluder
said connector means comprising a ball and collar assembly for allowing
relative movement between the first occluder and the second occluder
when said occluders are in the expanded configuration, said assembly
comprising a collar connected to one of the first and second occluders
with an aperture and a pin with a ball fitting connected to the other of the
first and second occluders on at least one end thereof wherein a diameter
of said ball fitting is larger than a diameter of the aperture in the collar.
’235 patent col.11 ll.39-61 (emphasis added).
B. The accused device
Cardia’s accused product works generally as described in the ’235 patent. It also
consists of two connected occluders which open to repair holes in cardiac tissue after
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delivery by catheter. To show noninfringement, Cardia argues that its connector—the
part of the accused device that links the two occluders and allows them to flex and
move relative to each other—does not embody the relevant limitations of any asserted
claim. The following diagram, Figure 8 of Cardia’s U.S. Patent No. 7,087,072, illustrates
the basic design of the accused device’s connector, though the figure does not
necessarily represent the accused device in all particulars:
In Cardia’s product, each occluder is fixed to a pin 74 and 72. On the opposite sides of
those pins are ball joints 120 and 130, nestled in sockets 114 and 112 in a central
sleeve or collar. The ball joints are larger than the openings 152 and 154, so the pins
cannot pull out of the socket, but they can both move within the joint to some extent.
Some of the debate on the issue of infringement relates to the different ways in
which the connector will allow the pins to move. The parties identify three different
modes of movement, designated by the terms “rotate,” “pivot,” and “translate.” In the
sense that the parties use these terms, the two pins of the accused device can
independently “rotate” (spin within the socket in a pinwheeling motion) and “pivot” (move
up-and-down or side-to-side in a hinge-like motion, like that of a human shoulder joint.)
The accused device’s connector allows “translation” (the ball moves deeper into the
collar or the reverse) only to a minimal extent, due to manufacturing tolerances.
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C. Procedural history
In an order dated August 29, 2006, the district court construed the asserted
claims and resolved the parties’ cross-motions for summary judgment in favor of Cardia,
concluding that there was no infringement.
Claim 1 recites a “connector means . . . comprising a pivot means.” The district
court used and construed the two phrases “connector means” and “pivot means”
interchangeably, determining them to be a means-plus-function limitation pursuant to 35
U.S.C. § 112, ¶ 6. Construction of a means-plus-function claim limitation requires the
court to identify the claimed function and then to locate structure in the specification
which has been clearly linked to that function. See Golight, Inc. v. Wal-Mart Stores,
Inc., 355 F.3d 1327, 1333-34 (Fed. Cir. 2004). Accordingly, the district court
determined that the claimed function was to allow the pins to rotate and pivot (again, in
the sense that those terms are used by the parties.) Cardia had argued that another
claimed function was to prevent the pins from translating, but the district court refused to
impose that function upon the claim. The district court then identified as corresponding
structure the embodiments illustrated by Figs. 5a, 5b, 5e, 5f, 5j, and 5k of the ’235
patent. It found the claims as construed not to be infringed, either literally or by
equivalents.
The district court concluded that the claim limitation of “a collar connected to one
of the first and second occluders” in claim 12 was not in means-plus-function form. It
construed that limitation to require “that the pin with a ball fitting be directly connected to
one occluder and the collar be directly connected to the other occluder.” Because in the
accused device the collar is connected only indirectly to the occluders—a ball joint and
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pin intervene—the district court concluded that Claim 12 was not literally infringed. It
also concluded that prosecution history estoppel barred assertion of the doctrine of
equivalents.
II. DISCUSSION
A. Standard of review
A determination of patent infringement requires a two-step analysis: first, the
meaning of the claim language is construed, then the claim as construed is compared to
the accused device in order to ascertain whether the device falls within its scope.
Markman v. Westview Instruments, Inc., 52 F.3d 967, 976 (Fed. Cir. 1995) (en banc).
We review the district court’s claim construction de novo. Cybor Corp. v. FAS Techs.,
Inc., 138 F.3d 1448, 1456 (Fed. Cir. 1998) (en banc). Summary judgment is also
reviewed de novo, Johns Hopkins Univ. v. Cellpro, Inc., 152 F.3d 1342, 1353 (Fed. Cir.
1998), and is proper “if the pleadings, depositions, answers to interrogatories, and
admissions on file, together with the affidavits, if any, show that there is no genuine
issue as to any material fact and that the moving party is entitled to a judgment as a
matter of law.” Fed. R. Civ. P. 56(c).
B. Claims 1-5
The disputed limitations of Claims 1-5 are in means-plus-function form; that is,
they are “expressed as a means or step for performing a specified function without the
recital of structure, material, or acts in support thereof.” 35 U.S.C. § 112 ¶ 6. As
mentioned above, the district court found that the function of the pivot means was to
“allow for both pivoting—that is, a hinge-like motion—and rotation—that is spinning—of
the first and second occluders with respect to each other.” It also explicitly found that
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“translation is not a claimed function.” Neither party challenges the district court’s
identification of those claimed functions.
Once a means-plus-function claim is construed, literal infringement is analyzed
by determining whether “the accused device employs structure identical or equivalent to
the structure disclosed in the patent and . . . the accused device performs the identical
function specified in the claim.” WMS Gaming Inc. v. Int’l Game Tech., 184 F.3d 1339,
1351 (Fed. Cir. 1999). That question is one of fact. IMS Tech., Inc. v. Haas
Automation, Inc., 206 F.3d 1422, 1430 (Fed. Cir. 2000). Therefore, summary judgment
of noninfringement requires a conclusion “that no reasonable jury could have found
otherwise.” Id.
The district court determined that no reasonable factfinder could find that
Cardia’s accused device was equivalent, as required by § 112 ¶ 6, to any of the
structures identified during the claim construction step. It therefore granted summary
judgment to Cardia. NMT challenges this finding on appeal. While the district court
identified several of the ’235 patent’s figures as corresponding structure to the “pivot
means” limitation, it noted that only Figures 5a and 5b allow rotation. On appeal, NMT
focuses on those two figures. It argues that a reasonable jury could find the connectors
depicted by those two figures to be only insubstantially different from the connector in
Cardia’s device.
The specification states that:
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Fig. 5a depicts an interconnection 50 in which individual collar elements
52, 54 are connected by a pin 56 having ball fittings 58 attached to the
ends thereof. The ball fitting[s] 58 are designed to be larger in diameter
than apertures 60, 62 contained within the collar members 52, 54 thereby
allowing the collars to move toward or away from each other while
preventing the pin 56 from being released therefrom.
’235 patent col.6 ll.32-39. The ball-and-collar joints depicted allow “[t]he collar members
. . . to rotate relative to each other.” Id. ll.42-43. Figure 5b depicts a simpler
arrangement where the pin 72 is fixed to the occluder on one side, and has only one
ball 48 on the other side which sits inside a single collar 54. Id. ll.57-62.
In its brief, Cardia argues that the embodiments depicted by these two figures do
not allow for pivoting. This is fundamentally a claim construction argument: if the
embodiments of Fig. 5a and 5b do not pivot, then they cannot supply structure which
performs the claimed pivoting function, and the district court would have erred by
identifying them as corresponding structure. We agree with NMT that these
embodiments do pivot at least to some extent. The apertures through which the pin
passes are shown as having wider diameters than the pin itself, which means that the
collars will be free to pivot until the pin’s contact with the sides of the aperture prevents
further movement. Indeed, Cardia’s own three-dimensional demonstrative of Fig. 5a
used at oral argument exhibited some pivoting motion.
In order to show that a means-plus-function claim is literally infringed, “the
patentee must establish that the accused device employs structure identical or
equivalent to the structure disclosed in the patent and that the accused device performs
the identical function specified in the claim.” WMS Gaming, 184 F.3d at 1350. There is
no dispute that the connector of Cardia’s accused device allows rotation and pivoting
and therefore performs the claimed functions, nor that Cardia’s device is not identical to
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any embodiment disclosed in the patent. The infringement issue therefore turns on
“whether the differences between the structure in the accused device and [the structure]
disclosed in the specification are insubstantial.” Id. at 1351.
Cardia argues that no reasonable jury could find the accused product equivalent
to the embodiments of Figs. 5a and 5b. It points out that the translation allowed by
those embodiments as the pin slides into and out of the collars will prevent the
occluders from sealing the defect tightly, resulting in undesirable blood leakage. Its
accused product, by contrast, allows only minimal translation attributable to
manufacturing tolerances and provides a better seal. Cardia also points out that the
fulcrum around which pivoting occurs in its device is located at the center of the ball in
its product, whereas in Figs. 5a and 5b the fulcrum is found somewhere on the pin.
Furthermore, Cardia’s device uses two balls in a central collar, an arrangement not
explicitly set forth anywhere in the ’235 patent. Cardia has therefore submitted
evidence tending to show that its accused device is different from the embodiments
disclosed in the ’235 patent. This evidence may well persuade a jury to find that the
differences between Cardia’s product and the identified structures are substantial.
It was error, however, to resolve the disputed factual question of substantiality in
the posture of summary judgment. A jury could also consider the similarities
demonstrated here: both the identified structure and the accused device use a ball
connected to a pin, and both place the ball within a socket which prevents the ball from
being pulled out. Both allow for rotation and pivoting. Whether the differences that
Cardia has highlighted are insubstantial in light of those similarities is a factual
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determination that cannot be resolved as a matter of law. There remains a triable issue
of fact on the question of substantial difference.
Accordingly, the summary judgment that Claim 1 was not infringed must be
vacated. Cardia makes no argument that its accused product lacks any of the
limitations added by dependent Claims 2-5, so we vacate the summary judgment as to
those claims as well.
C. Claim 12
NMT challenges the district court’s construction of Claim 12, arguing that the
requirement that the collar be connected “directly” to the occluder improperly narrowed
the claim. We agree with NMT that the district court erred by requiring this restriction.
As an initial matter, the ’235 patent’s specification demonstrates that the
patentees actually used the word “directly” when they meant to describe a direct
connection. For example, the specification describes Fig. 5e, below, as follows:
“In FIG. 5e, loops 82, 84 connected to individual occluder elements 12, 14 or 42, 44 are
connected by means of an interconnecting link 86 to form, generally, a three link chain
for interconnecting the individual occluder elements.” ’235 patent col.7 ll.33-37
(emphasis added). Contrast the specification’s description of Fig. 5i: “Unlike the
interconnection of FIG. 5h, the interconnection of FIG. 5i has replaced the pin with a
second connecting rod 132 that connects directly to an occluder element.” Id. col.8
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ll.15-18 (emphasis added). The description of Fig. 5k uses basically identical language
to describe a similar embodiment.
The specification therefore demonstrates that the patentees used the word
“directly” when they meant to specifically point out that a connection was direct.
Reading these claims in the context of the specification’s usage of language, see
Phillips v. AWH Corp., 415 F.3d 1303, 1315-17 (Fed. Cir. 2005) (en banc), there is no
reason on the face of the patent to limit Claim 12 to embodiments that connect
“directly.”
Cardia argues that the claims should nevertheless be limited because the
patentees disclaimed indirectly-connected embodiments during prosecution. See
Phillips, 415 F.3d at 1317 (“[T]he prosecution history can often inform the meaning of
the claim language by demonstrating . . . whether the inventor limited the invention in
the course of prosecution, making the claim scope narrower than it would otherwise
be.”) However, we have “declined to apply the doctrine of prosecution disclaimer where
the alleged disavowal of claim scope is ambiguous.” Omega Eng’g, Inc. v. Raytek
Corp., 334 F.3d 1314, 1324 (Fed. Cir. 2003).
Here, Cardia points out that what ultimately became Claim 12 of the ’235 patent
began prosecution reading simply “The device of claim 1 wherein the connector
comprises a ball and collar assembly.” The Examiner objected to this claim on
indefiniteness grounds, because “it [was] unclear how the ball is interrelated with the
collar, and how this assembly as a whole is connected to the occluders.” After two
amendments, the patentees were able to surmount the indefiniteness rejection by
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adding more detail about how the ball, collar, and occluders were interrelated. The
Examiner did not object on definiteness grounds to a claim reading:
The device of claim 1, wherein the connector means comprises a ball and
colar [sic] assembly, said assembly comprises a collar connected to one
of the first and second occluders with an aperture and a pin with a ball
fitting connected to the other of the first and second occluders on at least
one end thereof wherein a diameter of said ball fitting is larger that [sic] a
diameter of the aperture in the collar.
(emphasis added). Ultimately, this claim was rewritten into independent form and further
amended to issue as Claim 12.
The issue here is whether these amendments amount to an unambiguous
surrender of indirect connection. They do not. While the patentees added considerably
more detail about the relationship between the ball, collar, and occluders, the
amendments here do not refer at all to whether those relationships are direct in nature
or if the connections are made through intermediate parts. As noted above, the term
“connected” as used in the specification—the same specification which was before the
Examiner at the time of these amendments—does not necessarily imply direct
connection. When the patentees added limitations to their claim more specifically
describing the organization of their invention’s connected parts, they did not somehow
implicitly add other limitations about the specific nature of those connections.
Accordingly, the prosecution history provides no unambiguous basis to vary from
the meaning of the claims as read in light of the specification. The correct construction
of Claim 12 does not require “direct” connection between the enumerated parts. Since
the district court relied on an incorrect claim construction, its summary judgment of
noninfringement as to Claim 12 must be vacated.
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D. NMT’s request for summary judgment
NMT argues that we should award it summary judgment of infringement. This
court defers to the district court’s denial of summary judgment. See Suntiger, Inc. v.
Sci. Research Funding Group, 189 F.3d 1327, 1333 (Fed. Cir. 1999) (“When a district
court grants summary judgment, we review without deference to the trial court . . . . By
contrast, when a district court denies summary judgment, we review that decision with
considerable deference to the court.”). Accordingly, we decline NMT’s request to end
the case in its favor now, but on remand the district court may reconsider the question
of summary judgment for NMT based upon this court’s discussion of claim construction.
III. CONCLUSION
The summary judgment of noninfringement of claims 1-5 and 12 is vacated, and
the case is remanded to the district court for further proceedings consistent with this
opinion.
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