TRAFFIX DEVICES, INC. v. MARKETING DISPLAYS, INC.

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23 OCTOBER TERM, 2000
Syllabus
TRAFFIX DEVICES, INC. v. MARKETING
DISPLAYS, INC.
certiorari to the united states court of appeals for
the sixth circuit
No. 99–1571. Argued November 29, 2000—Decided March 20, 2001
Respondent, Marketing Displays, Inc. (MDI), holds now-expired utility
patents for a “dual-spring design” mechanism that keeps temporary
road and other outdoor signs upright in adverse wind conditions. MDI
claims that its sign stands were recognizable to buyers and users be-
cause the patented design was visible near the sign stand’s base. After
the patents expired and petitioner TrafFix Devices, Inc., began market-
ing sign stands with a dual-spring mechanism copied from MDI’s design,
MDI brought suit under the Trademark Act of 1946 for, inter alia, trade
dress infringement. The District Court granted TrafFix’s motion for
summary judgment, holding that no reasonable trier of fact could deter-
mine that MDI had established secondary meaning in its alleged trade
dress, i. e., consumers did not associate the dual-spring design’s look
with MDI; and, as an independent reason, that there could be no trade
dress protection for the design because it was functional. The Sixth
Circuit reversed. Among other things, it suggested that the District
Court committed legal error by looking only to the dual-spring design
when evaluating MDI’s trade dress because a competitor had to find
some way to hide the design or otherwise set it apart from MDI’s; ex-
plained, relying on Qualitex Co. v. Jacobson Products Co., 514 U. S. 159,
165, that exclusive use of a feature must put competitors at a significant
non-reputation-related disadvantage before trade dress protection is de-
nied on functionality grounds; and noted a split among the Circuits on
the issue whether an expired utility patent forecloses the possibility of
trade dress protection in the product’s design.
Held: Because MDI’s dual-spring design is a functional feature for which
there is no trade dress protection, MDI’s claim is barred. Pp. 28–35.
(a) Trade dress can be protected under federal law, but the person
asserting such protection in an infringement action must prove that the
matter sought to be protected is not functional, 15 U. S. C. § 1125(a)(3).
Trade dress protection must subsist with the recognition that in many
instances there is no prohibition against copying goods and products.
An expired utility patent has vital significance in resolving a trade dress
claim, for a utility patent is strong evidence that the features therein
claimed are functional. The central advance claimed in the expired util-

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24 TRAFFIX DEVICES, INC. v. MARKETING DISPLAYS, INC.
Syllabus
ity patents here is the dual-spring design, which is an essential feature
of the trade dress MDI now seeks to protect. However, MDI did not,
and cannot, carry the burden of overcoming the strong evidentiary infer-
ence of functionality based on the disclosure of the dual-spring design
in the claims of the expired patents. The springs are necessary to the
device’s operation, and they would have been covered by the claims of
the expired patents even though they look different from the embodi-
ment revealed in those patents, see Sarkisian v. Winn-Proof Corp., 697
F. 2d 1313. The rationale for the rule that the disclosure of a feature
in a utility patent’s claims constitutes strong evidence of functionality is
well illustrated in this case. The design serves the important purpose
of keeping the sign upright in heavy wind conditions, and statements
in the expired patent applications indicate that it does so in a unique
and useful manner and at a cost advantage over alternative designs.
Pp. 28–32.
(b) In reversing the summary judgment against MDI, the Sixth Cir-
cuit gave insufficient weight to the importance of the expired utility
patents, and their evidentiary significance, in establishing the device’s
functionality. The error was likely caused by its misinterpretation of
trade dress principles in other respects. “ ‘In general terms a product
feature is functional,’ and cannot serve as a trademark, ‘if it is essential
to the use or purpose of the article or if it affects the cost or quality of
the article.’ ” Qualitex, supra, at 165 (quoting Inwood Laboratories,
Inc. v. Ives Laboratories, Inc., 456 U. S. 844, 850, n. 10). This Court
has expanded on that meaning, observing that a functional feature is
one “the exclusive use of [which] would put competitors at a significant
non-reputation-related disadvantage,” Qualitex, supra, at 165, but that
language does not mean that competitive necessity is a necessary test
for functionality. Where the design is functional under the Inwood for-
mulation there is no need to proceed further to consider competitive
necessity. This Court has allowed trade dress protection to inherently
distinctive product features on the assumption that they were not func-
tional. Two Pesos, Inc. v. Taco Cabana, Inc., 505 U. S. 763, 774. Here,
however, beyond serving the purpose of informing consumers that the
sign stands are made by MDI, the design provides a unique and useful
mechanism to resist the wind’s force. Functionality having been estab-
lished, whether the design has acquired secondary meaning need not be
considered. Nor is it necessary to speculate about other design possi-
bilities. Finally, this Court need not resolve here the question whether
the Patent Clause of the Constitution, of its own force, prohibits the
holder of an expired utility patent from claiming trade dress protec-
tion. Pp. 32–35.
200 F. 3d 929, reversed and remanded.

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Opinion of the Court
Kennedy, J., delivered the opinion for a unanimous Court.
John G. Roberts, Jr., argued the cause for petitioner.
With him on the briefs were Gregory G. Garre and Jeanne-
Marie Marshall.
Deputy Solicitor General Wallace argued the cause for
the United States as amicus curiae urging reversal. With
him on the brief were Solicitor General Waxman, Assistant
Attorney General Ogden, Jeffrey A. Lamken, Anthony J.
Steinmeyer, and Mark S. Davies.
John A. Artz argued the cause for respondent. With him
on the brief were John S. Artz, Robert P. Renke, and Lisa
A. Sarkisian.*
Justice Kennedy delivered the opinion of the Court.
Temporary road signs with warnings like “Road Work
Ahead” or “Left Shoulder Closed” must withstand strong
gusts of wind. An inventor named Robert Sarkisian ob-
tained two utility patents for a mechanism built upon two
springs (the dual-spring design) to keep these and other out-
door signs upright despite adverse wind conditions. The
holder of the now-expired Sarkisian patents, respondent
Marketing Displays, Inc. (MDI), established a successful
business in the manufacture and sale of sign stands incorpo-
rating the patented feature. MDI’s stands for road signs
were recognizable to buyers and users (it says) because the
dual-spring design was visible near the base of the sign.
*Briefs of amici curiae urging reversal were filed for the Holmes Group,
Inc., by James W. Dabney; for Panduit Corp. by Roy E. Hofer, Jerome
Gilson, Cynthia A. Homan, and Philip A. Jones; and for Malla Pollack,
pro se.
Briefs of amici curiae urging affirmance were filed for the American
Intellectual Property Association by Louis T. Pirkey; and for Thomas &
Betts Corp. by Sidney David and Roy H. Wepner.
Theodore H. Davis, Jr., Marie V. Driscoll, and Helen Hill Minsker filed
a brief for the International Trademark Association as amicus curiae.

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26 TRAFFIX DEVICES, INC. v. MARKETING DISPLAYS, INC.
Opinion of the Court
This litigation followed after the patents expired and a
competitor, TrafFix Devices, Inc., sold sign stands with a
visible spring mechanism that looked like MDI’s. MDI and
TrafFix products looked alike because they were. When
TrafFix started in business, it sent an MDI product abroad
to have it reverse engineered, that is to say copied. Compli-
cating matters, TrafFix marketed its sign stands under a
name similar to MDI’s. MDI used the name “WindMaster,”
while TrafFix, its new competitor, used “WindBuster.”
MDI brought suit under the Trademark Act of 1946 (Lan-
ham Act), 60 Stat. 427, as amended, 15 U. S. C. § 1051 et seq.,
against TrafFix for trademark infringement (based on the
similar names), trade dress infringement (based on the cop-
ied dual-spring design), and unfair competition. TrafFix
counterclaimed on antitrust theories. After the United
States District Court for the Eastern District of Michigan
considered cross-motions for summary judgment, MDI pre-
vailed on its trademark claim for the confusing similarity of
names and was held not liable on the antitrust counterclaim;
and those two rulings, affirmed by the Court of Appeals, are
not before us.
I
We are concerned with the trade dress question. The
District Court ruled against MDI on its trade dress claim.
971 F. Supp. 262 (ED Mich. 1997). After determining that
the one element of MDI’s trade dress at issue was the dual-
spring design, id., at 265, it held that “no reasonable trier
of fact could determine that MDI has established secondary
meaning” in its alleged trade dress, id., at 269. In other
words, consumers did not associate the look of the dual-
spring design with MDI. As a second, independent reason
to grant summary judgment in favor of TrafFix, the District
Court determined the dual-spring design was functional.
On this rationale secondary meaning is irrelevant because
there can be no trade dress protection in any event. In rul-
ing on the functional aspect of the design, the District Court

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Opinion of the Court
noted that Sixth Circuit precedent indicated that the burden
was on MDI to prove that its trade dress was nonfunctional,
and not on TrafFix to show that it was functional (a rule
since adopted by Congress, see 15 U. S. C. § 1125(a)(3) (1994
ed., Supp. V)), and then went on to consider MDI’s argu-
ments that the dual-spring design was subject to trade dress
protection. Finding none of MDI’s contentions persuasive,
the District Court concluded MDI had not “proffered suf-
ficient evidence which would enable a reasonable trier of
fact to find that MDI’s vertical dual-spring design is non-
functional.” 971 F. Supp., at 276. Summary judgment was
entered against MDI on its trade dress claims.
The Court of Appeals for the Sixth Circuit reversed the
trade dress ruling. 200 F. 3d 929 (1999). The Court of Ap-
peals held the District Court had erred in ruling MDI failed
to show a genuine issue of material fact regarding whether
it had secondary meaning in its alleged trade dress, id., at
938, and had erred further in determining that MDI could
not prevail in any event because the alleged trade dress was
in fact a functional product configuration, id., at 940. The
Court of Appeals suggested the District Court committed
legal error by looking only to the dual-spring design when
evaluating MDI’s trade dress. Basic to its reasoning was
the Court of Appeals’ observation that it took “little imagi-
nation to conceive of a hidden dual-spring mechanism or
a tri or quad-spring mechanism that might avoid infring-
ing [MDI’s] trade dress.” Ibid. The Court of Appeals ex-
plained that “[i]f TrafFix or another competitor chooses to
use [MDI’s] dual-spring design, then it will have to find some
other way to set its sign apart to avoid infringing [MDI’s]
trade dress.” Ibid. It was not sufficient, according to the
Court of Appeals, that allowing exclusive use of a particular
feature such as the dual-spring design in the guise of trade
dress would “hinde[r] competition somewhat.” Rather,
“[e]xclusive use of a feature must ‘put competitors at a sig-
nificant non-reputation-related disadvantage’ before trade

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dress protection is denied on functionality grounds.” Ibid.
(quoting Qualitex Co. v. Jacobson Products Co., 514 U. S. 159,
165 (1995)). In its criticism of the District Court’s ruling on
the trade dress question, the Court of Appeals took note of
a split among Courts of Appeals in various other Circuits on
the issue whether the existence of an expired utility patent
forecloses the possibility of the patentee’s claiming trade
dress protection in the product’s design. 200 F. 3d, at 939.
Compare Sunbeam Products, Inc. v. West Bend Co., 123 F. 3d
246 (CA5 1997) (holding that trade dress protection is not
foreclosed), Thomas & Betts Corp. v. Panduit Corp., 138
F. 3d 277 (CA7 1998) (same), and Midwest Industries, Inc. v.
Karavan Trailers, Inc., 175 F. 3d 1356 (CA Fed 1999) (same),
with Vornado Air Circulation Systems, Inc. v. Duracraft
Corp., 58 F. 3d 1498, 1500 (CA10 1995) (“Where a product
configuration is a significant inventive component of an in-
vention covered by a utility patent . . . it cannot receive trade
dress protection”). To resolve the conflict, we granted cer-
tiorari. 530 U. S. 1260 (2000).
II
It is well established that trade dress can be protected
under federal law. The design or packaging of a product
may acquire a distinctiveness which serves to identify the
product with its manufacturer or source; and a design or
package which acquires this secondary meaning, assuming
other requisites are met, is a trade dress which may not be
used in a manner likely to cause confusion as to the origin,
sponsorship, or approval of the goods. In these respects
protection for trade dress exists to promote competition.
As we explained just last Term, see Wal-Mart Stores, Inc. v.
Samara Brothers, Inc., 529 U. S. 205 (2000), various Courts
of Appeals have allowed claims of trade dress infringement
relying on the general provision of the Lanham Act which
provides a cause of action to one who is injured when a per-
son uses “any word, term name, symbol, or device, or any

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combination thereof . . . which is likely to cause confusion . . .
as to the origin, sponsorship, or approval of his or her
goods.” 15 U. S. C. § 1125(a)(1)(A). Congress confirmed
this statutory protection for trade dress by amending the
Lanham Act to recognize the concept. Title 15 U. S. C.
§ 1125(a)(3) (1994 ed., Supp. V) provides: “In a civil action for
trade dress infringement under this chapter for trade dress
not registered on the principal register, the person who as-
serts trade dress protection has the burden of proving that
the matter sought to be protected is not functional.” This
burden of proof gives force to the well-established rule that
trade dress protection may not be claimed for product fea-
tures that are functional. Qualitex, supra, at 164–165; Two
Pesos, Inc. v. Taco Cabana, Inc., 505 U. S. 763, 775 (1992).
And in Wal-Mart, supra, we were careful to caution against
misuse or overextension of trade dress. We noted that
“product design almost invariably serves purposes other
than source identification.” Id., at 213.
Trade dress protection must subsist with the recognition
that in many instances there is no prohibition against copy-
ing goods and products. In general, unless an intellectual
property right such as a patent or copyright protects an
item, it will be subject to copying. As the Court has ex-
plained, copying is not always discouraged or disfavored by
the laws which preserve our competitive economy. Bonito
Boats, Inc. v. Thunder Craft Boats, Inc., 489 U. S. 141, 160
(1989). Allowing competitors to copy will have salutary ef-
fects in many instances. “Reverse engineering of chemical
and mechanical articles in the public domain often leads to
significant advances in technology.” Ibid.
The principal question in this case is the effect of an ex-
pired patent on a claim of trade dress infringement. A prior
patent, we conclude, has vital significance in resolving the
trade dress claim. A utility patent is strong evidence that
the features therein claimed are functional. If trade dress
protection is sought for those features the strong evidence

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of functionality based on the previous patent adds great
weight to the statutory presumption that features are
deemed functional until proved otherwise by the party seek-
ing trade dress protection. Where the expired patent
claimed the features in question, one who seeks to establish
trade dress protection must carry the heavy burden of show-
ing that the feature is not functional, for instance by showing
that it is merely an ornamental, incidental, or arbitrary as-
pect of the device.
In the case before us, the central advance claimed in the
expired utility patents (the Sarkisian patents) is the dual-
spring design; and the dual-spring design is the essential fea-
ture of the trade dress MDI now seeks to establish and to
protect. The rule we have explained bars the trade dress
claim, for MDI did not, and cannot, carry the burden of over-
coming the strong evidentiary inference of functionality
based on the disclosure of the dual-spring design in the
claims of the expired patents.
The dual springs shown in the Sarkisian patents were well
apart (at either end of a frame for holding a rectangular sign
when one full side is the base) while the dual springs at issue
here are close together (in a frame designed to hold a sign
by one of its corners). As the District Court recognized,
this makes little difference. The point is that the springs
are necessary to the operation of the device. The fact that
the springs in this very different-looking device fall within
the claims of the patents is illustrated by MDI’s own position
in earlier litigation. In the late 1970’s, MDI engaged in a
long-running intellectual property battle with a company
known as Winn-Proof. Although the precise claims of the
Sarkisian patents cover sign stands with springs “spaced
apart,” U. S. Patent No. 3,646,696, col. 4; U. S. Patent
No. 3,662,482, col. 4, the Winn-Proof sign stands (with
springs much like the sign stands at issue here) were found
to infringe the patents by the United States District Court
for the District of Oregon, and the Court of Appeals for the

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Ninth Circuit affirmed the judgment. Sarkisian v. Winn-
Proof Corp., 697 F. 2d 1313 (1983). Although the Winn-
Proof traffic sign stand (with dual springs close together) did
not appear, then, to infringe the literal terms of the patent
claims (which called for “spaced apart” springs), the Winn-
Proof sign stand was found to infringe the patents under
the doctrine of equivalents, which allows a finding of patent
infringement even when the accused product does not fall
within the literal terms of the claims. Id., at 1321–1322; see
generally Warner-Jenkinson Co. v. Hilton Davis Chemical
Co., 520 U. S. 17 (1997). In light of this past ruling—a ruling
procured at MDI’s own insistence—it must be concluded the
products here at issue would have been covered by the
claims of the expired patents.
The rationale for the rule that the disclosure of a feature
in the claims of a utility patent constitutes strong evidence of
functionality is well illustrated in this case. The dual-spring
design serves the important purpose of keeping the sign up-
right even in heavy wind conditions; and, as confirmed by
the statements in the expired patents, it does so in a unique
and useful manner. As the specification of one of the pat-
ents recites, prior art “devices, in practice, will topple under
the force of a strong wind.” U. S. Patent No. 3,662,482, col.
1. The dual-spring design allows sign stands to resist top-
pling in strong winds. Using a dual-spring design rather
than a single spring achieves important operational advan-
tages. For example, the specifications of the patents note
that the “use of a pair of springs . . . as opposed to the use
of a single spring to support the frame structure prevents
canting or twisting of the sign around a vertical axis,” and
that, if not prevented, twisting “may cause damage to the
spring structure and may result in tipping of the device.”
U. S. Patent No. 3,646,696, col. 3. In the course of patent
prosecution, it was said that “[t]he use of a pair of spring
connections as opposed to a single spring connection . . .
forms an important part of this combination” because it

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“forc[es] the sign frame to tip along the longitudinal axis of
the elongated ground-engaging members.” App. 218. The
dual-spring design affects the cost of the device as well; it
was acknowledged that the device “could use three springs
but this would unnecessarily increase the cost of the device.”
Id., at 217. These statements made in the patent applica-
tions and in the course of procuring the patents demonstrate
the functionality of the design. MDI does not assert that
any of these representations are mistaken or inaccurate, and
this is further strong evidence of the functionality of the
dual-spring design.
III
In finding for MDI on the trade dress issue the Court of
Appeals gave insufficient recognition to the importance of
the expired utility patents, and their evidentiary significance,
in establishing the functionality of the device. The error
likely was caused by its misinterpretation of trade dress
principles in other respects. As we have noted, even if
there has been no previous utility patent the party asserting
trade dress has the burden to establish the nonfunctionality
of alleged trade dress features. MDI could not meet this
burden. Discussing trademarks, we have said “ ‘[i]n general
terms, a product feature is functional,’ and cannot serve as
a trademark, ‘if it is essential to the use or purpose of the
article or if it affects the cost or quality of the article.’ ”
Qualitex, 514 U. S., at 165 (quoting Inwood Laboratories,
Inc. v. Ives Laboratories, Inc., 456 U. S. 844, 850, n. 10
(1982)). Expanding upon the meaning of this phrase, we
have observed that a functional feature is one the “exclusive
use of [which] would put competitors at a significant non-
reputation-related disadvantage.” 514 U. S., at 165. The
Court of Appeals in the instant case seemed to interpret this
language to mean that a necessary test for functionality is
“whether the particular product configuration is a competi-
tive necessity.” 200 F. 3d, at 940. See also Vornado, 58
F. 3d, at 1507 (“Functionality, by contrast, has been defined

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Opinion of the Court
both by our circuit, and more recently by the Supreme Court,
in terms of competitive need”). This was incorrect as a com-
prehensive definition. As explained in Qualitex, supra, and
Inwood, supra, a feature is also functional when it is essen-
tial to the use or purpose of the device or when it affects the
cost or quality of the device. The Qualitex decision did not
purport to displace this traditional rule. Instead, it quoted
the rule as Inwood had set it forth. It is proper to inquire
into a “significant non-reputation-related disadvantage” in
cases of esthetic functionality, the question involved in Qual-
itex. Where the design is functional under the Inwood for-
mulation there is no need to proceed further to consider if
there is a competitive necessity for the feature. In Quali-
tex, by contrast, esthetic functionality was the central ques-
tion, there having been no indication that the green-gold
color of the laundry press pad had any bearing on the use or
purpose of the product or its cost or quality.
The Court has allowed trade dress protection to certain
product features that are inherently distinctive. Two Pesos,
505 U. S., at 774. In Two Pesos, however, the Court at the
outset made the explicit analytic assumption that the trade
dress features in question (decorations and other features to
evoke a Mexican theme in a restaurant) were not functional.
Id., at 767, n. 6. The trade dress in those cases did not bar
competitors from copying functional product design features.
In the instant case, beyond serving the purpose of informing
consumers that the sign stands are made by MDI (assuming
it does so), the dual-spring design provides a unique and use-
ful mechanism to resist the force of the wind. Functionality
having been established, whether MDI’s dual-spring design
has acquired secondary meaning need not be considered.
There is no need, furthermore, to engage, as did the Court
of Appeals, in speculation about other design possibilities,
such as using three or four springs which might serve the
same purpose. 200 F. 3d, at 940. Here, the functionality of
the spring design means that competitors need not explore

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whether other spring juxtapositions might be used. The
dual-spring design is not an arbitrary flourish in the config-
uration of MDI’s product; it is the reason the device works.
Other designs need not be attempted.
Because the dual-spring design is functional, it is unneces-
sary for competitors to explore designs to hide the springs,
say, by using a box or framework to cover them, as suggested
by the Court of Appeals. Ibid. The dual-spring design as-
sures the user the device will work. If buyers are assured
the product serves its purpose by seeing the operative mech-
anism that in itself serves an important market need. It
would be at cross-purposes to those objectives, and some-
thing of a paradox, were we to require the manufacturer to
conceal the very item the user seeks.
In a case where a manufacturer seeks to protect arbitrary,
incidental, or ornamental aspects of features of a product
found in the patent claims, such as arbitrary curves in the
legs or an ornamental pattern painted on the springs, a dif-
ferent result might obtain. There the manufacturer could
perhaps prove that those aspects do not serve a purpose
within the terms of the utility patent. The inquiry into
whether such features, asserted to be trade dress, are func-
tional by reason of their inclusion in the claims of an expired
utility patent could be aided by going beyond the claims and
examining the patent and its prosecution history to see if the
feature in question is shown as a useful part of the invention.
No such claim is made here, however. MDI in essence seeks
protection for the dual-spring design alone. The asserted
trade dress consists simply of the dual-spring design, four
legs, a base, an upright, and a sign. MDI has pointed to
nothing arbitrary about the components of its device or the
way they are assembled. The Lanham Act does not exist
to reward manufacturers for their innovation in creating a
particular device; that is the purpose of the patent law and
its period of exclusivity. The Lanham Act, furthermore,
does not protect trade dress in a functional design simply

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35 Cite as: 532 U. S. 23 (2001)
Opinion of the Court
because an investment has been made to encourage the pub-
lic to associate a particular functional feature with a sin-
gle manufacturer or seller. The Court of Appeals erred in
viewing MDI as possessing the right to exclude competitors
from using a design identical to MDI’s and to require those
competitors to adopt a different design simply to avoid copy-
ing it. MDI cannot gain the exclusive right to produce sign
stands using the dual-spring design by asserting that con-
sumers associate it with the look of the invention itself.
Whether a utility patent has expired or there has been no
utility patent at all, a product design which has a particular
appearance may be functional because it is “essential to the
use or purpose of the article” or “affects the cost or quality
of the article.” Inwood, 456 U. S., at 850, n. 10.
TrafFix and some of its amici argue that the Patent
Clause of the Constitution, Art. I, § 8, cl. 8, of its own force,
prohibits the holder of an expired utility patent from claim-
ing trade dress protection. Brief for Petitioner 33–36; Brief
for Panduit Corp. as Amicus Curiae 3; Brief for Malla Pol-
lack as Amicus Curiae 2. We need not resolve this ques-
tion. If, despite the rule that functional features may not
be the subject of trade dress protection, a case arises in
which trade dress becomes the practical equivalent of an ex-
pired utility patent, that will be time enough to consider the
matter. The judgment of the Court of Appeals is reversed,
and the case is remanded for further proceedings consistent
with this opinion.
It is so ordered.