Ceramtec Gmbh v. Coorstek Bioceramics LLC, Fka C5 Medical Werks, LLC

United States Court of Appeals
for the Federal Circuit
______________________
CERAMTEC GMBH,
Appellant
v.
COORSTEK BIOCERAMICS LLC, FKA C5
MEDICAL WERKS, LLC,
Appellee
______________________
2023-1502
______________________
Appeal from the United States Patent and Trademark
Office, Trademark Trial and Appeal Board in Nos.
92058781, 92058796.
______________________
Decided: January 3, 2024
______________________
JESSICA LYNN ELLSWORTH, Hogan Lovells US LLP,
Washington, DC, argued for appellant. Also represented
by ANNA KURIAN SHAW, REEDY SWANSON; KATHERINE
BOOTH WELLINGTON, Boston, MA; JOHANNAH CASSEL-
WALKER, San Francisco, CA.
STEVEN J. HOROWITZ, Sidley Austin LLP, Chicago, IL,
argued for appellee. Also represented by CAROLINE A.
WONG; DIANA RUTOWSKI, Orrick, Herrington & Sutcliffe
LLP, Menlo Park, CA.
______________________
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CERAMTEC GMBH v. COORSTEK BIOCERAMICS LLC 2
Before LOURIE, TARANTO, and STARK, Circuit Judges.
LOURIE, Circuit Judge.
CeramTec GmbH (“CeramTec”) appeals from a decision
of the United States Trademark Trial and Appeal Board
(“the Board”) cancelling its trademarks which claim
protection for the pink color of ceramic hip components.
Coorstek Bioceramics LLC f/k/a C5 Medical Werks, LLC
v. CeramTec GmbH, Nos. 92058781 & 92058796, 2022 WL
17547263 (T.T.A.B. Dec. 6, 2022) (“Decision”). For the
reasons discussed below, we affirm.
BACKGROUND
CeramTec manufactures artificial hip components used
to replace damaged bone and cartilage in hip replacement
procedures. The hip components are made from a zirconia-
toughened alumina (“ZTA”) ceramic originally developed
for use in cutting tools. The ZTA ceramic contains, among
other things, chromium oxide (chromia). CeramTec
markets the hip components under the name, “Biolox
Delta.” Decision at *15.
Biolox Delta’s chemical composition, including the
addition of chromia, was the subject of CeramTec’s U.S.
Patent 5,830,816 (“the ’816 patent”) until January 2013,
when the patent expired. J.A. 1230. Claim element 3(e) of
the ’816 patent is illustrative, claiming “the molar ratio
between the [zirconia] . . . and the [chromia] amounting to
1,000:1 to 20:1.” ’816 patent col. 10, ll. 31–33. The ’816
patent’s specification and prosecution history discuss how
adding chromia enables the claimed composition to obtain
unprecedented levels of hardness. ’816 patent col. 3, ll. 62–
63 (the addition of chromia “makes it possible for the first
time to achieve hardness values such as have not
previously been achieved”); J.A. 1628 (’816 patent
prosecution history: similar)). Increased hardness levels
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Registration No. 4319095
hip joint ball
eRegistration No. 4319096
acetabular shell or fossa
CERAMTEC GMBH v. COORSTEK BIOCERAMICS LLC 3
enable the ZTA hip component to maintain its shape and
resist deformation. Decision at *13.
The amount of chromia in the ZTA ceramic affects its
coloring. In fact, the range of chromia claimed in the ’816
patent can produce ZTA ceramics in a variety of colors, such
as pink, red, purple, yellow, black, gray, and white. Biolox
Delta contains chromia at a 0.33 weight percentage
(0.33%), which makes it pink. Decision at *16, *56.
CeramTec has also applied for and received other patents
that spoke to chromia’s impact on ZTA ceramic hardness.
In January 2012, CeramTec applied for two
trademarks claiming protection for the color pink used in
ceramic hip components. In April 2013, the marks were
registered on the Supplemental Register.
Decision at *14; see also J.A. 107–10 (Supplemental
Registration Nos. 4319095 and 4319096).
CoorsTek Bioceramics LLC, formerly known as C5
Medical Werks, LLC (“CoorsTek”), is a competitor to
CeramTec in the medical-implant market. CoorsTek
manufactures two ZTA ceramic materials for hip implants:
(1) CeraSurf-p, which contains chromia, rendering it pink,
and (2) CeraSurf-w, which does not contain chromia,
rendering it white.
On March 3, 2014, CoorsTek filed a lawsuit in the
District of Colorado and a cancellation petition with the
Board, both seeking to cancel CeramTec’s trademarks on
the ground that the color pink claimed was functional. J.A.
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CERAMTEC GMBH v. COORSTEK BIOCERAMICS LLC 4
491–500.1 In response, at the Board, CeramTec argued
that although it had once believed that adding chromia
provided material benefits to ZTA ceramics, that belief was
mistaken and has since been disproven.
The Board found in favor of CoorsTek and concluded
that the color pink was functional as it relates to ceramic
hip components. Decision at *57. The Board analyzed the
functionality of the marks under the four factors discussed
in In re Morton–Norwich Products, Inc., 671 F.2d 1332,
1340–41 (C.C.P.A. 1982), and also considered experimental
testing conducted in a related German litigation,
suggesting that chromia has no effect on the material
properties of ZTA ceramic hip components. Id. at *48–57.
Applying the Morton–Norwich factors, the Board found
that CeramTec’s patents and public communications
disclosed that the addition of chromia provides material
benefits to ZTA ceramics, and therefore weighed in favor of
functionality. Id. at *49–54. Because there was no
probative evidence as to whether Biolox Delta would work
as well if made in colors apart from pink, the Board found
this factor to be neutral with respect to functionality. Id.
at *54. And because there was conflicting evidence as to
whether chromia decreases the cost of manufacturing
ceramic hip components, the Board also found this factor
neutral. Id. at *55.
As for the testing suggesting that chromia had no effect
on the material properties of ZTA ceramics, the Board
found the experiments to be methodologically flawed, and
1 The district court proceeding was ultimately
resolved on procedural grounds. C5 MedicalWerks, LLC vs.
CeramTec GmbH, 937 F.3d 1319, 1323 (10th Cir. 2019)
(vacating the district court decision based on a lack of
personal jurisdiction).
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CERAMTEC GMBH v. COORSTEK BIOCERAMICS LLC 5
therefore chose not to factor the results into its
functionality determination. Id. at *55–56.
Lastly, the Board rejected CeramTec’s unclean hands
defense, in which CeramTec argued that CoorsTek should
be precluded from petitioning to cancel its trademarks on
functionality grounds because CoorsTek had previously
contended that chromia provided no material benefits to
ZTA ceramics. Id. at *57–58.
In sum, the Board cancelled the marks based on its
conclusion that the marks are in fact functional. CeramTec
appeals the Board’s decision. We have jurisdiction under
28 U.S.C. § 1295(a)(4)(B) and 15 U.S.C. § 1071(a)(1).
DISCUSSION
A trademark is not registrable or is cancellable if the
design described is functional. See Valu Eng’g, Inc. v.
Rexnord Corp., 278 F.3d 1268, 1273 (Fed. Cir. 2002). As
the Supreme Court explained in Qualitex Co. v. Jacobson
Prods. Co.:
The functionality doctrine prevents trademark law,
which seeks to promote competition by protecting a
firm’s reputation, from instead inhibiting
legitimate competition by allowing a producer to
control a useful product feature. It is the province
of patent law, not trademark law, to encourage
invention by granting inventors a monopoly over
new product designs or functions for a limited time,
35 U.S.C. §§ 154, 173, after which competitors are
free to use the innovation. If a product’s functional
features could be used as trademarks, however, a
monopoly over such features could be obtained
without regard to whether they qualify as patents
and could be extended forever (because trademarks
may be renewed in perpetuity).
514 U.S. 159, 164–65 (1995).
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CERAMTEC GMBH v. COORSTEK BIOCERAMICS LLC 6
Legal conclusions of the Board are reviewed de novo,
and the factual findings of the Board are upheld when they
are supported by substantial evidence. In re Pacer Tech.,
338 F.3d 1348, 1349 (Fed. Cir. 2003). A finding is supported
by substantial evidence if a reasonable mind might accept
the evidence as adequate to support the finding. In re GO
& Assocs., LLC, 90 F.4th 1354, 1357 (Fed. Cir. 2024). The
functionality of a mark is a question of fact. In re Becton,
Dickinson & Co., 675 F.3d 1368, 1372 (Fed. Cir. 2012);
Morton–Norwich, 671 F.2d at 1340–41 (C.C.P.A. 1982)
(establishing the Morton–Norwich factors for evaluating
trademark functionality).
CeramTec raises two main arguments on appeal: (1)
that the Board’s finding that its trademarks are functional
was infected by legal error and unsupported by substantial
evidence, and (2) that the Board erred by categorically
precluding the defense of unclean hands in cancellation
proceedings involving functionality.
I
CeramTec first challenges the Board’s finding that its
trademarks are functional. CeramTec asserts that the
Board’s analysis with respect to the first Morton–Norwich
factor was both factually and legally flawed and that the
Board’s findings with respect to the third and fourth factors
were not supported by substantial evidence. CeramTec
also asserts that the Board’s findings as to the
experimental testing were not supported by substantial
evidence. And last, CeramTec contends that the Board
erroneously placed the burden on it to prove that its
trademarks were not functional. We address each
argument in turn.
A
As noted, the Board analyzed the functionality of
CeramTec’s trademarks in part under the four factors set
out in Morton–Norwich, 671 F.2d at 1340–41:
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CERAMTEC GMBH v. COORSTEK BIOCERAMICS LLC 7
(1) the existence of a utility patent disclosing the
utilitarian advantages of the design;
(2) advertising materials in which the originator of
the design touts the design’s utilitarian
advantages;
(3) the availability to competitors of functionally
equivalent designs; and
(4) facts indicating that the design results in a
comparatively simple or cheap method of
manufacturing the product.
1
The Board concluded that CeramTec’s patents were
“strong evidence that the color pink for ceramic hip implant
components is functional” under the first Morton–Norwich
factor. Decision at *52. In analyzing the first factor, the
Board read the claims, specification, and prosecution
history of the ’816 patent to disclose the “functional
benefits of chromia with respect to the toughness,
hardness, stability and suppression of brittleness of the
ZTA ceramic.” Id. at *51. The Board also considered
CeramTec’s other patents and applications, e.g., U.S.
Patent 9,237,955 (“the ’955 patent”) and U.S. Patent
Application 2012/0142237 (“the ’237 application”), which it
found disclosed that chromia increases the hardness and
toughness of ZTA ceramics and makes ZTA ceramics
suitable for medical applications. Id. And last, the Board
considered CeramTec’s concessions that the addition of
chromia causes ZTA ceramics to become pink and that
Biolox Delta practices at least one claim of the ’816 patent.
Id.
CeramTec makes two arguments challenging the
Board’s analysis under the first Morton–Norwich factor: (1)
that the Board erred in reading the patents to attribute
functional benefits to the addition of chromia other than
hardness, and (2) that the Board improperly applied the
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CERAMTEC GMBH v. COORSTEK BIOCERAMICS LLC 8
Supreme Court’s decision in TrafFix Devices, Inc. v. Mktg.
Displays, Inc., 532 U.S. 23 (2001) to the facts of this case.
CeramTec contends that it was error for the Board to
find that the patents disclose that chromia provides
utilitarian advantages to ZTA ceramics in addition to
increasing hardness. Although the patents mention other
material benefits (toughness, stability, and suppression of
brittleness), CeramTec asserts that the patents attribute
them to other elements of ZTA ceramics (e.g., zirconia).
CeramTec, however, admits that the Board correctly read
the ’816 patent to attribute increased hardness levels of
ZTA ceramics to the addition of chromia. CeramTec Br. at
10 (the “[’816] patent, reflecting the understanding at the
time, suggests that chromia in the amounts claimed
contributes to the overall hardness of the ZTA ceramic”).
We therefore need not consider whether the Board may
have partially erred in its reading of the patents because
the Board’s analysis is equally supported whether the
patents state that chromia accounts for only one or several
material benefits.
As for TrafFix, CeramTec acknowledges that that case
holds that utility patents can be “strong evidence” that the
features therein claimed are functional, thus precluding
trademark protection. However, CeramTec argues that
TrafFix only applies when two threshold requirements are
met. First, according to CeramTec, the utility patent must
explicitly claim a design feature that the patent owner
later seeks to trademark, and second, the goods for which
trademark protection is sought must be the “central
advance” of the patent—i.e., the same goods mentioned in
the patent. CeramTec asserts neither requirement is met
here because the patents do not explicitly disclose material
benefits for pink ZTA ceramics and do not discuss hip
components, only cutting tools.
CeramTec supports its reading of TrafFix by pointing to
the policy underlying the functionality doctrine. According
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CERAMTEC GMBH v. COORSTEK BIOCERAMICS LLC 9
to CeramTec, the reason patented design features weigh in
favor of finding a trademark functional is “because the
public should be ‘free to use’ those features after the
patent’s terms have ended.” Reply Br. at 12 (quoting
Qualitex, 514 U.S. at 164). And here, CeramTec contends
that the public is free to use CeramTec’s patents, so long as
it does not “produc[e] a pink product.” Reply Br. at 12. We
disagree with CeramTec’s reading of TrafFix.
In TrafFix, the Supreme Court explained that because
utility patents are granted for “unique and useful”
inventions, they are “strong evidence that the features
therein claimed are functional.” TrafFix, 532 U.S. at 29,
31. Accordingly, “if trade[mark] protection is sought for
those features[,]” the patent “great[ly] weigh[s]” in favor of
finding the trademark functional. Id. at 29–30. TrafFix
also explained that the functionality inquiry can be “aided
by . . . examining the patent [specification] and its
prosecution history to see if the feature in question is
shown as a useful part of the invention.” Id. at 34. But
nowhere does TrafFix hold that for a patent to be evidence
of a claimed feature’s functionality, the patent must
explicitly disclose that the claimed feature is functional.
Nor does TrafFix state that for a trademark to be subject
to a TrafFix analysis it must be used for the goods
described in the patent. Rather, the “central advance”
language was used by the TrafFix Court to illustrate why
the patent in that case was particularly strong evidence
that the design feature at issue was functional. See id. at
30.
The Board correctly applied TrafFix here. Recall
CeramTec’s two concessions: (1) the addition of chromia
causes a ZTA ceramic to become pink, and (2) that Biolox
Delta practices at least one claim of the ’816 patent.
Decision at *51. These concessions establish that the ’816
patent claims a “feature[],” the color pink, which CeramTec
has trademarked. TrafFix, 532 U.S. at 30. The Board also
considered the specifications and prosecution history of the
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CERAMTEC GMBH v. COORSTEK BIOCERAMICS LLC 10
’816 patent, which state that the addition of chromia
increases ZTA ceramic hardness. Decision at *51; ’816
patent col. 3, ll. 61–63 (the addition of chromia “makes it
possible for the first time to achieve hardness values such
as have not previously been achieved”); J.A. 1628 (’816
patent prosecution history: similar). And the Board
supported its conclusion with CeramTec’s other patents,
which also disclose that chromia increases ZTA ceramic
hardness. ’955 patent col. 7. ll 33–35 (“[T]he chromium
addition counteracts any drop in the hardness values when
the proportion of zirconium dioxide rises.”); see also ’237
application, Abstract, (the addition of chromia to a ZTA
ceramic is “particularly suitable for medi[c]al application”).
CeramTec’s policy argument is likewise unpersuasive.
The functionality doctrine is premised on the public being
“free to use the innovation” after a patent has expired—not
merely a part of the innovation. Qualitex, 514 U.S. at 164.
That CeramTec only seeks to prevent the public (i.e.,
CoorsTek) from practicing the narrow portion of its patents
that claim a pink ZTA ceramic is beside the point.
Permitting the public to use that innovation weighs in
favor of finding functionality.
The Board therefore did not err in evaluating the first
factor.
2
The Board found that the second Morton–Norwich
factor—advertising materials in which the originator of the
design touts the design’s utilitarian advantages—also
“constitute[s] strong evidence of functionality.” Decision at
*54. In coming to this conclusion, the Board considered
promotional and technical literature, as well as
submissions made to the FDA, in which CeramTec stated
that chromia provides various functional benefits to ZTA
ceramics. Id. at 52–53.
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CERAMTEC GMBH v. COORSTEK BIOCERAMICS LLC 11
CeramTec does not challenge the Board’s finding with
respect to factor two. We accordingly need not review that
ruling and turn to the Board’s analysis of the third factor.
3
The Board found the third factor—the availability of
functionally equivalent designs—to be neutral with respect
to functionality. Id. at 54. That finding was supported by
substantial evidence.
As the Board recognized, there was no “probative
evidence” that different-colored ceramic hip components
were “equivalent in desired ceramic mechanical properties
to those of [Biolox Delta].” Id. That lack of evidence was
critical—for the third factor to weigh in favor of non-
functionality, there must be evidence of actual or potential
alternative designs “that work equally well” to the
trademarked design. Valu Eng’g, 278 F.3d at 1276
(citation omitted).
CeramTec contends that the Board’s neutral
determination was erroneous because the Board
overlooked undisputed evidence of actual and potential
ceramic hip components that are at least functionally
equivalent to Biolox Delta: (1) statements made by
CoorsTek that CeraSurf-w (CoorsTek’s white ceramic hip
component) was functionally better than Biolox Delta, and
(2) the ’816 patent, which can produce ZTA ceramics in a
variety of colors in addition to pink. CeramTec
mischaracterizes both the evidence and the Board’s
analysis.
First, the evidence did not undisputedly provide that
CeraSurf-w was functionally better than Biolox Delta.
CoorsTek’s employee proffered that CeraSurf-w “is not as
hard” as CeraSurf-p (CoorsTek’s pink ceramic), and thus
not functionally better than Biolox Delta. Decision at *40;
J.A. 4911.
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CERAMTEC GMBH v. COORSTEK BIOCERAMICS LLC 12
Second, as for the ’816 patent, the Board began its
analysis of the third factor by stating, “because of the
technical challenges involved[,] there are only a few
companies” capable of producing ceramic hip components.
Decision at *54. That suggests to us that the Board simply
discounted all potential alternative designs because they
are too theoretical. CeramTec’s argument thus amounts to
a disagreement with the weight the Board assigned to the
evidence, which we see no reason to disturb. See GO &
Assocs., 90 F.4th at 1357 (“reweighing the evidence is not
the role of this court”) (internal quotation marks and
citation omitted).
The Board’s determination that the third factor was
neutral was therefore supported by substantial evidence.
4
The Board also found the fourth Morton–Norwich
factor—whether the design results in a comparatively
simple or cheap method of manufacturing the product—to
be neutral. Decision at *55.
As with the third factor, CeramTec again argues that
the Board overlooked undisputed evidence providing that
chromia makes Biolox Delta more expensive to
manufacture, and therefore reversibly erred in not finding
the fourth factor to weigh in favor of non-functionality.
Once again, however, CeramTec mischaracterizes the
evidence as undisputed. As the Board noted, CoorsTek
proffered evidence that the cost of producing CeraSurf-p
was “pretty similar” to its white components. Id. at 55; J.A.
13527. Accordingly, in light of the conflicting evidence, the
Board reasonably found the factor to not weigh for or
against functionality. See GO & Assocs., 90 F.4th at 1357.
The Board’s determination that the fourth factor was
neutral was therefore supported by substantial evidence.
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CERAMTEC GMBH v. COORSTEK BIOCERAMICS LLC 13
B
Next, the Board properly considered and rejected the
results of several experiments conducted in a related
German litigation in which a government-sponsored
research agency found that the addition of chromia at
various levels (0.0, 0.1, 0.3, and 0.5% by weight) had no
effect on Biolox Delta’s hardness or wear resistance. Id. at
*39, *55–56.
The Board decided not to factor the results into its
functionality determination for two reasons. First, the
Board explained that it found CoorsTek’s expert’s
criticisms of the testing’s methodology to be “persuasive.”
Id. at *55. And second, the Board found that the
independent testing was incomplete because it did not
address the full range of chromia that produces pink ZTA
ceramics as claimed by the ’816 patent. Id. The Board
based the second critique on an internal CeramTec
experiment demonstrating that chromia at levels above
0.5% by weight causes ZTA ceramics to become the pink
color claimed in CeramTec’s trademarks whereas the
German-based testing did not evaluate levels above 0.5%
by weight. Id.
CeramTec takes issue with both reasons the Board gave
for discounting the results of the testing. With regard to
the Board’s statement that it found CoorsTek’s expert
persuasive, CeramTec argues that explanation was
inadequate because it did not give the findings of the
testing the “close attention” they deserved and ignored
CeramTec’s expert’s rebuttal report, which provided a
“point-for-point accounting” explaining why CoorsTek’s
expert’s criticisms were misguided. CeramTec Br. at 44,
46. This, however, overlooks that the Board devoted an
entire section of its opinion to discussing the methodology
of the testing and both parties’ expert’s opinions of the
testing. Decision at *39. CeramTec’s argument thus again
amounts to a disagreement with the weight the Board
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CERAMTEC GMBH v. COORSTEK BIOCERAMICS LLC 14
assigned to results of the independent testing, a finding
which we have no basis to disturb. See GO & Assocs., 90
F.4th at 1357.
CeramTec next contends that the Board’s criticism of
the independent testing was inapposite because CoorsTek’s
functionality challenge is to the exact amount of chromia
used to produce Biolox Delta, 0.33% by weight, within the
range of added chromia analyzed in the independent
testing. That argument is misguided: the issue before the
Board was whether the color pink claimed in CeramTec’s
trademarks is functional. The trademarks are not tied to
a specific amount of chromia. Decision at *1 (“The sole
claim for protection in each registration is for the color pink
only.”). CeramTec’s own internal experiment
demonstrated that the pink color of ZTA ceramics claimed
in its trademarks could be obtained at weight percentages
above 0.5%. Decision at *56; J.A. 10624. The Board
therefore acted in accord with its role as factfinder in
deciding to discount the results of the independent testing
as incomplete.
C
CeramTec’s last argument regarding the Board’s
functionality determination is that the Board erroneously
required it, the trademark owner, to prove that its
trademarks were not functional. In support of its position,
CeramTec points to the Board’s emphasis on certain
language in its discussion of the Supreme Court’s decision
in TrafFix. E.g., Decision at *50 (“Where the expired
patent claimed the features in question, one who seeks to
establish trade dress protection must carry the heavy
burden of showing that the feature is not functional[.]”)
(quoting TrafFix, 532 U.S. at 29–30 (emphasis added by
the Board)).
We are unpersuaded. The Board stated that
“[CoorsTek] bears the burden of proving its Trademark Act
Section 23(c) functionality claim by a preponderance of the
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CERAMTEC GMBH v. COORSTEK BIOCERAMICS LLC 15
evidence.” Decision at *2. After considering the evidence,
the Board concluded that CoorsTek “ha[d] carried [its]
burden” of proving that CeramTec’s trademarks are
functional. Id. It correctly applied the burden of proof.
We accordingly see no reason to disturb the Board’s
findings based on CeramTec’s burden shifting argument.
* * *
In sum, because substantial evidence supports the
Board’s factual findings, we affirm the Board’s conclusion
that CeramTec’s trademarks are functional.
II
We last consider the unclean hands issue. The doctrine
of unclean hands “closes the doors of a court of equity to
one tainted with inequitableness or bad faith relative to the
matter in which he seeks relief, however improper may
have been the behavior of the defendant.” Gilead Scis., Inc.
v. Merck & Co., 888 F.3d 1231, 1239 (Fed. Cir. 2018)
(quoting Precision Instrument Mfg. Co. v. Auto. Maint.
Mach. Co., 324 U.S. 806, 814 (1945)).
CeramTec argued to the Board that CoorsTek should
be precluded from asserting that CeramTec’s trademarks
are functional because CoorsTek had long expressed the
opposite: that chromia provides no material benefits for
ZTA ceramics. J.A. 617–21. The Board disagreed,
“hold[ing] . . . the unclean hands defense is unavailable in
Board functionality proceedings in view of the prevailing
public interest in removing registrations of functional
marks from the register” and “find[ing] [CeramTec’s]
unclean hands defense inapplicable.” Decision at *58.
CeramTec contends that the Board erred, necessitating
remand, by “refus[ing] to even consider the equitable
circumstances” and “adopt[ing] a categorical rule”
precluding the unclean hands defense in functionality
proceedings. CeramTec Br. at 61.
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CERAMTEC GMBH v. COORSTEK BIOCERAMICS LLC 16
We agree that the Board spoke too strongly by
suggesting that the unclean hands defense was
categorically unavailable in functionality proceedings. The
Board’s rules explicitly provide that the defendant, in
cancellation proceedings before the Board, may “includ[e]
the affirmative defense[] of unclean hands.” 37 C.F.R. §
2.114(b)(2). It is not clear that the Board intended to
announce a broad policy, as its conclusion is preceded by
reference to its “discretion,” which is generally exercised
case-by-case, and the Board did not designate its decision
as precedential. If, however, the Board intended to bar an
unclean hands defense from all functionality proceedings,
that would be error. Any such error was harmless here
because the Board adequately considered whether the
unclean hands defense was available in this case, as
illustrated by its statement that it was “exercis[ing its]
discretion” in view of the “strong public policy interest in”
cancelling ineligible marks. Decision at *58 (citing Loglan
Inst., Inc. v. Logical Language Grp., Inc., 962 F.2d 1038,
1042 (Fed. Cir. 1992) (“The Board did not err in declining
to apply [equitable] defenses [in a cancellation proceeding],
as the public interest . . . to rid the register of [an ineligible
mark] transcends them.”)).
CONCLUSION
We have considered CeramTec’s remaining arguments
and find them unpersuasive. For the foregoing reasons, we
affirm the final decision of the Board.
AFFIRMED
Case: 23-1502 Document: 43 Page: 16 Filed: 01/03/2025

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