The US Supreme Court issued a decision on March 20, 2001 concerning the effect of claimed subject matter in an expired utility patent on trade dress protection. Traffix Devices, Inc. v. Marketing Displays, Inc. 532 U.S. 23 (2001) involved two expired patents issued to Robert Sarkisian (US Pat. Nos. 3,646,696 issued March 7, 1972 and 3,662,482 issued May 16, 1972) involving a dual spring mechanism installed at the base of a sign to allow the sign flexibility in the wind. At issue was whether the design choices for placement of this dual spring mechanism were functional so as to preclude trade dress protection.

Marketing Displays, the assignee of the two Sarkisian patents, brought a trade dress infringement suit against Traffix Devices after the Sarkisian patents expired. Marketing Displays asserted that Traffix Devices was infringing Marketing Displays’ trade dress by producing signs with a dual spring mechanism at the base, which Marketing Displays claimed was a visually recognizable feature of its signs. The United States District Court for the Eastern District of Michigan had earlier dismissed Marketing Displays’ case at summary judgment saying the design was functional and thus not subject to trade dress protection. 971 F.Supp. 262. This decision was overturned by the Court of Appeals for the Sixth Circuit who said the district court judge made a legal error by not considering the feasibility for Traffix Devices to implement design alternatives other than the dual spring mechanism to serve the necessary wind flexibility function. 200 F.3d 929.

The US Supreme Court took on this issue to determine the extent to which a claimed element in a patent renders that element functional. In holding the dual spring design to be functional and thus precluding trade dress protection, the Court stated that: "[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 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 seeking trade dress protection." 121 S.Ct. 1255, 1260.

One argument made by Traffix Devices about which the Court explicitly declined to decide concerned the Patent Clause of the U.S. Constitution. Traffix Devices argued that Article I, Section 8, Clause 8 of the Constitution prohibits the holder of an expired utility patent from claiming trade dress protection as such protection would unconstitutionally extend the monopoly power of the patent. The Court left this issue for another day.