Document ID: s3://data.kl3m.ai/documents/govinfo/USCOURTS/USCOURTS-ca13-23-01502/USCOURTS-ca13-23-01502-0/pdf.json

Parties Involved:
CeramTec GmbH
Appellant
CoorsTek Bioceramics LLC
Appellee

Document Text:

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 CASSELWALKER, 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.

 ______________________

Case: 23-1502 Document: 43 Page: 1 Filed: 01/03/2025
2 CERAMTEC GMBH v. COORSTEK BIOCERAMICS LLC

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 zirconiatoughened 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 

Case: 23-1502 Document: 43 Page: 2 Filed: 01/03/2025
Registration No. 4319095 

hip joint ball 

e 

Registration 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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4 CERAMTEC GMBH v. COORSTEK BIOCERAMICS LLC

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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6 CERAMTEC GMBH v. COORSTEK BIOCERAMICS LLC

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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8 CERAMTEC GMBH v. COORSTEK BIOCERAMICS LLC

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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10 CERAMTEC GMBH v. COORSTEK BIOCERAMICS LLC

’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 nonfunctionality, 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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12 CERAMTEC GMBH v. COORSTEK BIOCERAMICS LLC

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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14 CERAMTEC GMBH v. COORSTEK BIOCERAMICS LLC

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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16 CERAMTEC GMBH v. COORSTEK BIOCERAMICS LLC

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