In Tiffany and Co. v. Costco Wholesale Corp., the US District Court for the Southern District of New York denied Tiffany's motion for summary judgment on Costco's counterclaim seeking a judgment that "tiffany" is a generic term for certain types of ring settings (No. 13 Civ. 1041, (S.D.N.Y. Jan 17, 2014)).

Tiffany holds 97 trademarks relating to the Tiffany name, including for the word "Tiffany" and for the stylized mark "Tiffany" covering jewelry, both first used in commerce in 1868. Tiffany claims that it calls one style of engagement ring it sells, a diamond solitaire in a six-prong setting, a "Tiffany® Setting" ring. Tiffany sued Costco for federal and NY state trademark infringement, dilution and other claims after Costco began using "Tiffany" in the name of two styles of engagement rings. The rings were not manufactured by Tiffany. Costco filed a counterclaim asserting that "Tiffany" is a generic term for engagement ring settings "comprised of multiple slender prongs extending upward from a base to hold a single gemstone." The counterclaim sought dismissal of the lawsuit and declarations, judgments and decrees that, among other things:

Tiffany filed alternative motions for summary judgment or dismissal under Federal Rule of Civil Procedure 12(c), which the SDNY treated as a motion for summary judgment.

The SDNY noted that a court may partially cancel or limit a trademark registration where only one use of the term has become generic. The court denied Tiffany's motion, finding that Costco's evidence was sufficient to raise a factual dispute whether "Tiffany" or "Tiffany Setting" has a primarily generic meaning for ring settings in the minds of the general public. Costco's evidence included: