The case is Tiffany & Co. and Tiffany (NJ) LLC v. Costco Wholesale Corp., the claim is intellectual property infringement. The United States’ largest warehouse club chain is being sued for selling alleged counterfeit diamond engagement rings bearing the name “Tiffany”. The belief is that hundreds, even thousands, of said engagement rings were sold to Costco members that were supposedly under the impression that the jewelry was in fact a Tiffany & Co. product.

The lawsuit is premised on the common plea that imitation products, such as the rings in this case, take away from Tiffany’s stream of revenue. Tiffany & Co. is seeking damages in the amount of $2 million per ring sold as well as profit forfeiture from Costco.

An investigation of a Costco store in Huntington Beach revealed that the store did in fact have engagement rings in its jewelry display cases with a label that said “Tiffany” in front of the rings. The same products were also detected on Costco’s website, also sans any Tiffany trademarks.

Despite the legal scuffle, both corporations experienced an increase in stock prices Friday afternoon; Tiffany & Co. up 91 cents and Costco up 45 cents.

Reportedly Costco executives or spokesmen have yet to comment.

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