Stryker v. Zimmer

United States Court of Appeals
for the Federal Circuit
______________________

STRYKER CORPORATION, STRYKER PUERTO
RICO, LTD., STRYKER SALES CORPORATION,
Plaintiffs-Appellees

v.

ZIMMER, INC., ZIMMER SURGICAL, INC.,
Defendants-Appellants

ZIMMER ORTHOPAEDIC SURGICAL PRODUCTS,
Defendant
______________________

2013-1668
______________________

Appeal from the United States District Court for the
Western District of Michigan in No. 10-CV-1223, Judge
Robert J. Jonker.
______________________

Decided: December 19, 2014
Revised Opinion Issued: March 23, 2015
______________________

GREGORY J. VOGLER, McAndrews, Held & Malloy,
Ltd., of Chicago, Illinois, argued for plaintiffs-appellees.
With him on the brief were SHARON A. HWANG, DEBORAH
A. LAUGHTON, and CAROLINE A. TEICHNER.

DONALD R. DUNNER, Finnegan, Henderson, Farabow,
Garrett & Dunner, LLP, of Washington, DC, argued for
2 STRYKER CORPORATION v. ZIMMER, INC.

defendants-appellants. With him on the brief were KARA
STOLL and GARTH BAER. Of counsel was BENJAMIN
THOMAS SIROLLY.
______________________

Before PROST, Chief Judge, NEWMAN and HUGHES, Circuit
Judges.
PROST, Chief Judge.
Zimmer, Inc., Zimmer Surgical, Inc., and Zimmer Or-
thopaedic Surgical Products (collectively “Zimmer”) ap-
peal from the final judgment of the United States District
Court for the Western District of Michigan that U.S.
Patent Nos. 6,022,329 (“’329 patent”), 6,179,807 (“’807
patent”), and 7,144,383 (“’383 patent”) were valid and
willfully infringed. For the reasons stated below, we
affirm the jury’s findings that the patents were valid and
infringed, and the jury’s award of damages to plaintiff-
appellees Stryker Corporation, Stryker Puerto Rico, Ltd.,
and Stryker Sales Corporation (collectively “Stryker”).
However, we reverse the district court’s judgment that
Zimmer’s infringement was willful, and, accordingly, we
vacate its award of treble damages. Finally, we vacate
and remand the district court’s finding of exceptional case
and its award of attorneys’ fees.
I
The patents at issue concern pulsed lavage devices.
Pulsed lavage devices deliver pressurized irrigation for
certain medical therapies, including orthopedic proce-
dures and cleaning wounds. The particular devices at
issue in this case are portable, battery powered, and
handheld. They include both suction and discharge tubes,
so they both spray fluid from an external source and also
suction off fluid and debris. These devices represent an
improvement over older pulsed lavage systems that
required a central power source and external mechanical
 STRYKER CORPORATION v. ZIMMER, INC. 3

pumps, which meant that they needed to be wheeled
around the hospital.
Stryker and Zimmer are the two main competitors in
the orthopedic pulsed lavage device market. Stryker
began bringing battery-powered, handheld pulsed lavage
devices to the marketplace in 1993. That same year,
Stryker filed the application which eventually gave rise to
the patents at issue. In February 2000, the first of these
patents, the ’329 patent, issued. Later that year Stryker
sued another manufacturer, Davol Inc., for infringement.
That suit settled in 2001, and Davol took a license on the
’329 patent. The ’807 patent subsequently issued in
January 2001, and the ’383 patent issued in December
2006.
Zimmer introduced its first portable pulsed lavage de-
vice, the Var-A-Pulse, in 1996. In 1998, Zimmer began to
develop a new design, which came to market soon thereaf-
ter as the Pulsavac Plus range of products. Zimmer’s
Pulsavac Plus products achieved a peak of $55 million in
annual sales in late 2007, before they were withdrawn
from the marketplace due to a product recall, after which
sales resumed in December 2008.
In 2010, Stryker sued Zimmer, alleging that Zimmer’s
Pulsavac Plus devices infringed various claims of the ’329,
’807, and ’383 patents. The district court granted partial
summary judgment in favor of Stryker, finding infringe-
ment of the ’807 and ’383 patents’ asserted claims. The
question of whether Zimmer infringed the single asserted
claim of the ’329 patent, as well as Zimmer’s invalidity
defenses against all of the asserted claims, went to trial.
The jury found that the products infringed claim 2 of the
’329 patent and that all the asserted claims were valid.
The jury also awarded $70 million in lost profits. It
further found that Zimmer had willfully infringed all
three patents. The jury also found that Stryker had
marked substantially all of its products that commercially
4 STRYKER CORPORATION v. ZIMMER, INC.

embodied the patents in suit during the period it sought
damages, pursuant to 35 U.S.C. § 287(a).
In August 2013, the district court issued an order re-
jecting Zimmer’s motions for judgment as a matter of law
(“JMOL”) on various issues, affirming the jury’s verdict,
awarding trebled damages for willful infringement, find-
ing an exceptional case and thus awarding attorneys’ fees
to Stryker, and imposing a permanent injunction. The
district court subsequently entered final judgment pursu-
ant to its order.
Zimmer appeals. We have jurisdiction under 28
U.S.C. § 1295(a)(1).
II
We turn first to Zimmer’s appeal on the issues of
claim construction, infringement, and validity.
Claim construction is an issue of law that we review
de novo. Lighting Ballast Control LLC v. Philips Elecs. N.
Am. Corp., 744 F.3d 1272, 1276-77 (Fed. Cir. 2014) (en
banc). In construing a claim term, we look at the term’s
plain and ordinary meaning as understood by a person of
ordinary skill in the art. Phillips v. AWH Corp., 415 F.3d
1303, 1313 (Fed. Cir. 2005) (en banc). There is an excep-
tion to this general rule when a patentee sets out a defini-
tion and acts as her own lexicographer. Thorner v. Sony
Computer Entm’t Am., LLC, 669 F.3d 1362, 1365 (Fed.
Cir. 2012). Infringement is a question of fact. Lucent
Techs., Inc. v. Gateway, Inc., 580 F.3d 1301, 1309 (Fed.
Cir. 2009). Invalidity by reason of anticipation under 35
U.S.C. § 102 is a question of fact. Atlas Powder Co. v.
Ireco, Inc., 190 F.3d 1342, 1346 (Fed. Cir. 1999). Invalidi-
ty by reason of obviousness under 35 U.S.C. § 103 is a
legal conclusion based on underlying facts. Allergan, Inc.
v. Sandoz Inc., 726 F.3d 1286, 1290 (Fed. Cir. 2013).
Zimmer has the burden to prove invalidity by clear and
 STRYKER CORPORATION v. ZIMMER, INC. 5

convincing evidence. Galderma Labs., L.P. v. Tolmar,
Inc., 737 F.3d 731, 736 (Fed. Cir. 2013).
On the issues of infringement and validity that the ju-
ry decided, Zimmer appeals the district court’s denials of
its motion for JMOL. Generally, a district court grants
JMOL and sets aside the jury’s verdict if it “finds that a
reasonable jury would not have a legally sufficient eviden-
tiary basis to find for the party on that issue.” Fed. R.
Civ. P. 50(a). We apply the law of the regional circuit to
our review of the district court’s grant or denial of a
motion for JMOL. ClearValue, Inc. v. Pearl River Poly-
mers, Inc., 668 F.3d 1340, 1343 (Fed. Cir. 2012). The
Sixth Circuit reviews the district court’s decision on a
motion for JMOL de novo. Barnes v. City of Cincinnati,
401 F.3d 729, 736 (6th Cir. 2005). “Judgment as a matter
of law may only be granted if, when viewing the evidence
in a light most favorable to the non-moving party, giving
that party the benefit of all reasonable inferences, there is
no genuine issue of material fact for the jury, and reason-
able minds could come to but one conclusion in favor of
the moving party.” Id.
For the reasons stated below, we affirm the district
court’s judgment on the various defenses of non-
infringement and invalidity that Zimmer raises across the
three asserted patents. However, we also find that each
of these defenses was not unreasonable.
The ’329 Patent
The only asserted claim of the ’329 patent, claim 2,
describes features of a “pulsed irrigation surgical hand-
piece.” According to this claim, the handpiece comprises a
“hollow housing,” which includes a “handle,” and, in
relevant part in this case, “an electric motor spaced
between the top and bottom of said handle and located in
said handle” adjacent to an irrigation tube within the
housing. ’329 patent col. 22 ll. 5-7 (emphases added).
Zimmer contends that this limitation is critical for the
6 STRYKER CORPORATION v. ZIMMER, INC.

purposes of infringement because, as indicated by the
arrows below, the motor in its accused Pulsavac Plus
device is not located in the handle—rather, it is located in
the “nub” of the handpiece, the protrusion behind the
barrel.

Appellees’ Br. 11 (red arrows added).
During claim construction, Zimmer took the position
that no construction was necessary and that the claim
term “handle” could be understood as having its plain and
ordinary meaning to a person of ordinary skill in the art.
Stryker Corp. v. Zimmer, Inc., No. 10-1223, slip op. at 6
(W.D. Mich. Feb. 1, 2012), ECF No. 106 (“Claim Construc-
tion Order”). Stryker proposed to construe the term
“handle” as “a portion of a device designed to be held by a
hand or hands.” Id. The district court adopted Stryker’s
proposed construction.
Stryker argued that nothing in the patent’s specifica-
tion otherwise limited the meaning of “handle,” and that
its definition for “handle” was consistent with general
dictionaries. Zimmer argued that Stryker’s express
construction of the term, however, was too broad and read
out the specification’s consistent distinction between the
“handle” and “barrel” portions of the claimed device.
The ’329 patent generally describes various embodi-
ments, all of which comprise a “hand-held housing having
 STRYKER CORPORATION v. ZIMMER, INC. 7

a handle and a barrel which extends from the upper end
of the handle.” ’329 patent col. 3 ll. 28-31. Zimmer fur-
ther supported its position with the language of claim 4,
which depends on claim 2. Claim 4 separately describes
both a “handle” and a “barrel,” which Zimmer argued
meant that the patentee maintained the distinction
between the two parts of the handpiece.
However, the district court ultimately agreed with the
Stryker that a device that met claim 2 did not need to
have a discrete barrel joined to the handle, since this
claim could cover wand-shaped devices that existed in the
prior art in which the entire handpiece functioned like a
handle and no separate barrel was joined at an angle.
The district court reasoned that since claim 4 is a depend-
ent claim, it could cover the pistol-shaped design de-
scribed in the specification, while claim 2 would more
broadly cover wand-shaped devices as well.
On appeal, Zimmer also raises the prosecution history
of U.S. Patent Application No. 08/559,133 (“’133 applica-
tion”), the parent of the application that issued as the ’329
patent. During the ’133 application’s prosecution, Stryker
sought to overcome a rejection of claim 39 based on a prior
art reference which described a pistol-shaped device with
a barrel and a handle. Stryker traversed the rejection by
arguing that the motor of the prior art handpiece was “not
in the handle or at an angle to the barrel.” Zimmer
contends that claim 39 included the limitation “locating
said motor in said handle,” which is the same as the one
at issue in the construction of “handle” in claim 2 of the
’329 patent. Therefore, Zimmer argues, Stryker’s state-
ment disclaimed designs in which the motor is located in
the barrel or nub of a pistol-shaped handpiece. See Ge-
malto S.A. v. HTC Corp., 754 F.3d 1364, 1371 (Fed. Cir.
2014) (“[W]hen multiple patents derive from the same
initial application, the prosecution history regarding a
claim limitation in any patent that has issued applies
with equal force to subsequently issued patents that
8 STRYKER CORPORATION v. ZIMMER, INC.

contain the same claim limitation.”); Microsoft Corp. v.
Multi-Tech Sys., Inc., 357 F.3d 1340, 1349 (Fed. Cir.
2004); Elkay Mfg. Co. v. EBCO Mfg. Co., 192 F.3d 973,
980 (Fed. Cir. 1999).
Zimmer did not raise its prosecution history argument
during its claim construction briefing and the Markman
hearing before the district court. The district court indi-
cated that it would not alter the claim construction but,
nevertheless, determined that it would still consider this
argument in deciding Zimmer’s motion for summary
judgment of non-infringement. Stryker Corp. v. Zimmer,
Inc., No. 10-1223, slip op. at 3 (W.D. Mich. Nov. 29, 2012),
ECF No. 248 (“Summary Judgment Order I”). The dis-
trict court nevertheless denied Zimmer’s motion, finding
that the prosecution disclaimer was insufficiently “clear
and unmistakable” because claim 39 of the ’133 applica-
tion had additional limitations that were absent in claim
2 of the ’329 patent. Id. at 4-5.
The district court’s analysis was flawed, however, be-
cause this was not a case in which the “purported dis-
claimers are directed to specific claim terms that have
been omitted or materially altered in subsequent applica-
tions (rather than to the invention itself).” Saunders
Grp., Inc. v. Comfortrac, Inc., 492 F.3d 1326, 1333 (Fed.
Cir. 2007). 1 There was no difference in the language

1 The limitation at issue in the original claim 39 of
the ’133 application was, in full: “a handpiece housing
containing said pump and shell, said handpiece housing
being elongate [sic] and bent and comprising a handle and
a barrel, said barrel being open to and extending forward
from an intersection with the top of the handle at an
angle thereto, said hollow shell extending lengthwise
along and within said handle into said angled intersection
of said handle and barrel and locating said motor in said
 STRYKER CORPORATION v. ZIMMER, INC. 9

describing the limitations as between the two claims at
issue, rather, the limitation of claim 2 was included
within claim 39. There is no reason why a disclaimer on a
limitation within a narrower claim would not apply to the
identical limitation within the broader claim, as the same
concerns about the prior art would relate to both. See,
e.g., Gemalto, 754 F.3d at 1371 (applying a common
disclaimer to both an independent and narrower depend-
ent claim containing the same term). 2 That said, the
district court did not err in rejecting Zimmer’s argument
as it related to claim construction, while still entertaining
it in the context of infringement. See SuperGuide Corp. v.
DirecTV Enters., Inc., 358 F.3d 870, 889-90 (Fed. Cir.
2004) (affirming the district court’s construction on the
grounds that a proffered alternative construction was

handle remote from said angled intersection, said link
extending at said angle from said shell and handle for-
wardly into and along the length direction of said barrel,
said pump movable member extending along the length
direction of said barrel and being reciprocatingly driven
by said link in said length direction of said barrel.” J.A.
16672 (emphasis added).

2 This is unlike the case cited by Stryker and the
district court for the contrary proposition, Middleton, Inc.
v. Minnesota Mining and Manufacturing. Co., 311 F.3d
1384, 1388-89 (Fed. Cir. 2002), in which the term at issue,
“uniform” in the context of floor coverings, would poten-
tially have a different meaning if it applied to the narrow-
er claim—limited to smooth sporting surfaces—and a
subsequent, broader claim that contemplated other kinds
of surfaces. Here, a limitation on the location of the motor
within the handpiece would mean the same thing in the
context of either claim.
10 STRYKER CORPORATION v. ZIMMER, INC.

untimely raised). Therefore, we review Zimmer’s argu-
ment only as it relates to infringement.
Infringement is a question of fact, and we must give a
substantial degree of deference to the jury’s verdict. At
trial, Stryker presented evidence indicating that a medi-
cal professional could hold Zimmer’s Pulsavac Plus by the
nub behind the barrel, where the motor was located. In
addition, Stryker presented evidence that the barrel of
the Pulsavac Plus was called a “barrel grip” in an associ-
ated patent application, and the barrel included indenta-
tions that would allow the device to be used while held by
the barrel. Stryker also persuaded the jury that it was
reasonable to infer that if the nub behind the barrel was
also shaped such that it was at least capable of being
held, then it would be “a portion of the device designed to
be held by hand,” in accordance with the district court’s
construction of “handle” in the claim at issue. In light of
the evidence presented at trial as a whole, along with the
prosecution history, we do not find that “reasonable minds
could come to but one conclusion” that Zimmer did not
infringe claim 2 of the ’329 patent. Barnes, 401 F.3d at
736. Accordingly, we affirm, though Zimmer’s claim
construction and non-infringement positions were not
unreasonable.
The ’807 Patent
Infringement
Zimmer argues that the district court erred in grant-
ing summary judgment of infringement of the ’807 pa-
tent’s asserted claims. We review the district court’s
grant of summary judgment de novo. Dixon v. Univ. of
Toledo, 702 F.3d 269, 273 (6th Cir. 2012). “Summary
judgment is proper where there exists no issue of material
fact and the moving party is entitled to judgment as a
matter of law.” ETW Corp. v. Jireh Publ’g, Inc., 332 F.3d
915, 920 (6th Cir. 2003) (citing Fed. R. Civ. P. 56(c)). All
 STRYKER CORPORATION v. ZIMMER, INC. 11

reasonable factual inferences are drawn in favor of the
nonmoving party. Id.
Zimmer’s argument on appeal centers on whether its
products include, as required for all the asserted claims,
“a front end for receiving the discharge tube and the
suction tube.” ’807 patent col. 27 ll. 35-37 (emphasis
added). 3 This limitation describes the interface between
the nozzles at the front end of the handpiece and the
nozzles of a removable tip that includes discharge and
suction tubes. Zimmer argues that the claim language
requires that there be male openings on the tip that fit
into the female nozzles on the handpiece. Therefore,
Zimmer contends that the accused devices do not infringe
because they are designed with female openings on the tip
that fit into tapered male nozzles on the handpiece. To
support its position, Zimmer relies on various dictionary
definitions of “receive,” which it argues all have some
variant of the verbs “to contain” or “to hold.” See Appel-
lants’ Br. 57. Zimmer argues that this meaning is con-
sistent with the specification, which discloses a single
embodiment in which the neck of the suction tube “seats
in” the drain tube—and, specifically, that this configura-
tion is designed to avoid “leakage of the fluid and material
as it flows in the drain tube.” ’807 patent col. 11 ll. 29-34;
see also Figure 8.
As an initial matter, Stryker’s argument that Zimmer
waived a narrower construction of the term “receive” is
unavailing. The parties and the district court directly
addressed this issue during the summary judgment
proceedings. Moreover, unlike the dispute concerning the
meaning of “handle” in the ’329 patent, the district court
did not note any waiver and expressly considered the

3 Stryker asserted claim 45 and certain of its de-
pendent claims.
12 STRYKER CORPORATION v. ZIMMER, INC.

scope of “receive” in evaluating whether Zimmer’s design
infringed. See Pfizer, Inc. v. Teva Pharm., USA, Inc., 429
F.3d 1364, 1377 (Fed. Cir. 2005) (contemplating “rolling
claim construction, in which the court revisits and alters
its interpretation of the claim terms as its understanding
of the technology evolves”).
Stryker further argues that the specification provides
a broader disclosure of “an irrigation handpiece to which
complementary tips can be readily coupled.” ’807 patent
col. 1 ll. 10-12 (emphasis added); see also col. 2 ll. 45-47
(disclosing “a tip assembly [that] readily seals to a com-
plementary handpiece”) (emphasis added). Stryker also
points to Zimmer’s own lay witnesses, who admitted that
its Pulsavac Plus handpiece “receives” the tips. 4
The district court noted that, in its view, “Zimmer’s
reading of ‘receive’ is artificially narrow.” Stryker Corp. v.
Zimmer, Inc., No. 10-1223, slip op. at 8 (W.D. Mich. Nov.
29, 2012), ECF No. 247 (“Summary Judgment Order II”).
Instead, the district court reasoned that “[t]he word
“receives” in this context can only mean that one part of
the device connects directly with another part of the
device.” Id. Thus, the district court found that Zimmer
infringed. While it is a close case, we do not find that the
district court erred in granting summary judgment of
infringement based on the record before it.

4 Stryker also argues that Zimmer’s invalidity ar-
gument relies on the prior art Var-A-Pulse device includ-
ing the “receive” limitation—even though it has the same
kind of tip assembly as the Pulsavac Plus. We note,
however, that nothing precludes Zimmer from arguing for
a narrower application of the limitation on the infringe-
ment context, while also arguing, in the alternative,
that—if the district court were to disagree—the patent
claim would be so broad as to be invalid.
 STRYKER CORPORATION v. ZIMMER, INC. 13

Invalidity
Zimmer also appeals the district court’s holding that
the asserted claims of the ’807 patent were anticipated by
its prior art Var-A-Pulse device, the predecessor of the
Pulsavac Plus. Stryker argues that the Var-A-Pulse
device does not anticipate because it is missing the “lock
assembly” limitation of the asserted claims, which require
that there be “a lock assembly mounted to the front end of
said body for releasably securing the discharge tube and
the suction tube to said body.” ’807 patent col. 27 ll. 35-
37. The district court adopted Stryker’s proposed con-
struction of the term “lock assembly” as “components that
work together to secure or fasten the tip to the hand-
piece.” Claim Construction Order at 16. In the Var-A-
Pulse device, the tip was attached to the handpiece in
such a way that the tip nozzles fit into interior housing
grooves at the front of the handpiece, which were then
held together by friction. Zimmer argues that under the
district court’s construction, the limitation was present in
the prior art because the nozzles were “secured or fas-
tened” when they were fit in the interior housing groove.
At trial, Zimmer presented evidence that included the
Var-A-Pulse’s technical documentation, which indicated
that the tip should be “secured” to the handpiece, as well
as testimony from various Stryker witnesses admitting
that the tip nozzles were fastened to the handpiece when
they were inserted. Stryker argued that, unlike the
accused Pulsavac Plus devices, which include a locking
ring to secure the tip, there is no separate part or assem-
bly in the Var-A-Pulse. Stryker also contended the prior
art device did not include the full claim limitation, which
requires that the lock assembly be “mounted” to the front
end of handpiece. Stryker argued that because Zimmer
identified a “lock assembly” that itself included the hous-
ing groove that is part of the front end, Zimmer was
essentially arguing that the lock assembly was mounted
to itself, thus nullifying the limitation. Stryker also
14 STRYKER CORPORATION v. ZIMMER, INC.

presented evidence to the jury showing that the Var-A-
Pulse tips readily fell off the front end of the handpiece,
and that this led the development of the locking ring in
the Pulsavac Pulse.
The jury ultimately found that there was no clear and
convincing evidence that the Var-A-Pulse device antici-
pated the ’807 patent’s asserted claims. In light of the
evidence that was presented, we find that a reasonable
jury could have reached this verdict. Accordingly, we
affirm.
The ’383 Patent
At trial, Zimmer argued that the asserted claims of
the ’383 patent were obvious at the time of the invention
in light of U.S. Patent No. 5,046,486 (“Grulke”), U.S.
Patent No. 4,817,599 (“Drews II”), and U.S. Patent No.
5,350,356 (“Bales”). Zimmer contends that all of the
limitations of the ’383 patent’s asserted claims were
collectively present in the prior art references. Stryker
does not directly dispute this point. Instead, it principally
argues that because the designs claimed by Grulke and
Drews II each exclude certain components described in
the claims, one of ordinary skill in the art would not have
been motivated to combine these references. In brief,
Grulke disclosed a pulsed lavage system that uses a
pneumatic, rather than an electric, motor. Drews II
disclosed a pulsed irrigation system, powered by an
electric motor, that is used as an eye wash.
At trial, Zimmer argued that it would have been obvi-
ous to one of ordinary skill to try to replace the pneumatic
motor of Grulke with the electric motor in Drews II.
Zimmer further argued that any reconfiguration of Grulke
to accommodate an electric motor could be done by one of
ordinary skill. See In re ICON Health & Fitness, Inc., 496
F.3d 1374, 1382 (Fed. Cir. 2007) (“[W]e do not ignore the
modifications that one skilled in the art would make to a
device borrowed from the prior art.”). Zimmer also argued
 STRYKER CORPORATION v. ZIMMER, INC. 15

that even though the Grulke reference was directed to
orthopedic pulsed lavage systems, and the Drews II
reference was directed to eyewash systems, they both
described pressured water irrigation in hospitals and
clinics. Zimmer contended that that a person of ordinary
skill in the art of pulsed lavage devices would thus be
aware of the art in both fields and would be motivated to
combine features from each of them. See KSR Int’l Co. v.
Teleflex Inc., 550 U.S. 398, 420 (2007) (“Common sense
teaches, however, that familiar items may have obvious
uses beyond their primary purposes, and in many cases a
person of ordinary skill will be able to fit the teachings of
multiple patents together like pieces of a puzzle.”).
Zimmer also presented evidence of the examiner’s re-
jection of certain claims in Stryker’s prosecution of U.S.
Patent Application No. 11/563,504 (“’504 application”), a
continuation of the ’383 patent, which occurred during the
discovery phase of this case. During that patent applica-
tion’s prosecution, the examiner issued a non-final office
action, rejecting certain claims of the ’504 application as
obvious over Grulke “and further in view of Drews II.”
J.A. 17226. Stryker did not attempt to traverse the
rejection and instead ultimately abandoned the applica-
tion. Stryker principally argued that because the claim at
issue in the ’504 application included certain different
limitations, the examiner’s rejection did not have any
relevance to the ’383 patent’s claims. We note, however,
that the difference in the detail of the claims is immateri-
al as to whether it would have been obvious to combine
Grulke and Drews II. While persuasive, the examiner’s
proffered rejection is not on its own dispositive, in large
part because the U.S. Patent and Trademark Office
(“PTO”) and district courts “take different approaches in
determining invalidity and on the same evidence could
quite correctly come to different conclusions.” Ethicon,
Inc. v. Quigg, 849 F.2d 1422, 1428 (Fed. Cir. 1988).
16 STRYKER CORPORATION v. ZIMMER, INC.

Stryker also argued that the Grulke device differed
substantially from the Drews II device. For example, it
was designed for surgery rather than eyewashing. Grulke
also disclosed a large device that was wheeled into an
operating room that had many components that differed
from those in the portable device disclosed Drews II.
Stryker presented expert testimony rebutting Zimmer’s
evidence that it would have been obvious to combine these
references.
On the basis of the record presented at trial, we agree
with the district court that a reasonable jury could con-
clude that one of ordinary skill in the art would not have
been motivated to combine the Grulke and Drews II
references, even in light of the examiner’s rejection of
related claims on the basis of this combination. This is
sufficient to affirm the district court’s determination that
Zimmer did not show, by clear and convincing evidence,
that the ’383 patent’s claims were obvious.
For this reason, we need not reach other issues, in-
cluding the evidence of secondary considerations of non-
obviousness. Therefore, we affirm the district court’s
determination that the ’383 patent’s asserted claims were
not obvious over the combination of Grulke, Drews II, and
Bales. 5

5 Zimmer also appeals the jury’s finding that
Stryker’s products were sufficiently marked by the ’383
patent during part of the period for which it sought dam-
ages. We need not reach this issue, because we affirm the
finding that Zimmer infringed the ’807 and ’329 patents,
which is sufficient to support all of Stryker’s award of
damages for lost profit. However, we note that the jury
was indeed incorrectly instructed that it should consider
“whether some portion of the Stryker products not
 STRYKER CORPORATION v. ZIMMER, INC. 17

III
Willful Infringement
To establish willful infringement, the patentee has
the burden of showing “by clear and convincing evidence
that the infringer acted despite an objectively high likeli-
hood that its actions constituted infringement of a valid
patent.” In re Seagate Tech., LLC, 497 F.3d 1360, 1371
(Fed. Cir. 2007) (en banc). “The state of mind of the
accused infringer is not relevant to this objective inquiry.”
Id. Only if the patentee establishes this “threshold objec-
tive standard” does the inquiry then move on to whether
“this objectively-defined risk (determined by the record
developed in the infringement proceeding) was either
known or so obvious that it should have been known to
the accused infringer.” Id. We have held that objective
recklessness, even though “predicated on underlying
mixed questions of law and fact, is best decided by the

marked with a particular patent number were marked
with other related patent notices.” Stryker Corp. v. Zim-
mer, Inc., No. 10-1223, slip op. at 18 (W.D. Mich. Aug. 7,
2013), ECF No. 537 (“Post-Verdict Order”) (emphasis
added). Because of this instruction, the jury could have
been misled to consider a product marked with the num-
ber of a patent related to the ’383 patent—but not with
the ’383 patent number itself—as being sufficiently
marked. While the district court appears to have relied
on cases that suggest that there is some flexibility in what
constitutes sufficient marking, the statute is not so broad
as to allow marking with a different patent—with differ-
ent claims—to provide sufficient notice to the public.
Rather, the plain language of the marking statute pro-
vides that the patented article be marked with the “num-
ber of the patent.” 35 U.S.C § 287(a) (emphasis added).
18 STRYKER CORPORATION v. ZIMMER, INC.

judge as a question of law subject to de novo review.” 6
Bard Peripheral Vascular, Inc. v. W.L. Gore & Assocs.,
Inc., 682 F.3d 1003, 1007 (Fed. Cir. 2012). Objective
recklessness will not be found where the accused infring-
er’s “position is susceptible to a reasonable conclusion of
no infringement.” Uniloc USA, Inc. v. Microsoft Corp.,
632 F.3d 1292, 1310 (Fed. Cir. 2011).
The district court failed to undertake an objective as-
sessment of Zimmer’s specific defenses to Stryker’s
claims. Instead, the district court’s analysis of objective
reasonableness summarily asserted that the “jury heard
testimony” that Zimmer “all but instructed its design
team to copy Stryker’s products.” Post-Verdict Order at
23. The district court further concluded that the “pioneer-
ing” nature of Stryker’s inventions and the secondary
considerations of non-obviousness “made it dramatically
less likely that Zimmer’s invalidity arguments were
reasonable.” Id.
An objective assessment of the case shows that Zim-
mer presented reasonable defenses to all of the asserted
claims of Stryker’s patents.

6 This court has not yet addressed whether Octane
Fitness, LLC v. ICON Health & Fitness, Inc., 134 S. Ct. 1749
(2014), or Highmark Inc. v. Allcare Health Mgmt. Sys., Inc., 134 S.
Ct. 1744, 1746 (2014), altered the standard of review under which
this court analyzes the objective prong of willfulness. However, as
the district court failed to undertake any objective assessment of
Zimmer’s specific defenses, the district court erred under any
standard of review and thus this court need not now address what
standard of review is proper regarding the objective prong of
willfulness.
 STRYKER CORPORATION v. ZIMMER, INC. 19

First, with respect to the ’329 patent, the motor in the
Zimmer’s Pulsavac Plus is located in the nub at the rear
of the barrel of its pistol-shaped device. Stryker’s in-
fringement case relied on first persuading the district
court to broadly construe the claim term “handle” to
include the barrel of a pistol-shaped device—even though
the patent specification only describes the handle and
barrel separately. Then, Stryker had to persuade the jury
that the barrel nub was a part of the device “designed to
be held by hand,” even in light of prosecution history in
which Stryker distinguished between the location of the
motor in the handle as opposed to the barrel. Though
Stryker ultimately prevailed, Zimmer’s arguments were
not unreasonably founded on the plain meaning of “han-
dle” in the context of a pistol-shaped device, the specifica-
tion’s exclusive disclosure of pistol-shaped devices, and
the prosecution history—all on which it could have relied
to provide notice of what the patent claims covered.
Second, with respect to the ’807 patent, the specifica-
tion only disclosed female nozzles on the front end of the
device and male nozzles on the removable tip, which
would be consistent with the claim requiring that the
front end “receive” the tip. Zimmer’s devices had the
exact opposite configuration: tapered male nozzles on the
front end and female nozzles on the tip. Furthermore, the
prior art Var-A-Pulse devices included all of the asserted
claims’ limitations except one. In light of the district
court’s claim construction, Stryker’s defense to Zimmer’s
argument relied on persuading the jury that even though
the tip’s nozzles could fit into the handpiece and be held
in place through friction with internal housing grooves,
that did not mean they were “secured or fastened.” Again,
though Stryker prevailed, Zimmer’s defenses were not
unreasonable.
Third, with respect to the ’383 patent, Zimmer’s obvi-
ousness argument relied on a combination of references
that was also raised by a PTO examiner during Stryker’s
20 STRYKER CORPORATION v. ZIMMER, INC.

prosecution of a related patent application—in an office
action that occurred during discovery in this litigation.
Zimmer’s reliance on this combination was not without
reason, in particular since the references related to pres-
sured water irrigation systems used in hospitals and
clinics. Therefore, even if Zimmer’s defenses failed at
trial, it still made a reasonable case that the ’383 patent’s
asserted claims were obvious and thus invalid.
In sum, we find that Zimmer’s defenses to the in-
fringement of each patent claim that Stryker asserted
were not objectively unreasonable, and, therefore, it did
not act recklessly.
Attorneys’ Fees
As the court reversed the district court’s determina-
tion of willful infringement, and the district court’s award
of attorneys’ fees was based on that determination, we
vacate the district court’s grant of attorneys’ fees. How-
ever, because there exist further allegations of litigation
misconduct in this case and because the standard for
finding an exceptional case has changed since the district
court issued its finding regarding attorneys’ fees, we
remand this issue for further consideration by the district
court.
IV
For the aforementioned reasons, we affirm the jury’s
verdict of infringement and validity of all three patents at
issue, as well as its award of lost profits. However, we
reverse the district court’s determination of willful in-
fringement and thus vacate its award of trebled damages.
We also vacate and remand the district court’s finding of
an exceptional case and its award of attorneys’ fees. The
case is remanded for further proceedings consistent with
this opinion.
AFFIRMED-IN-PART, REVERSED-IN-PART,
VACATED-IN-PART, AND REMANDED