11:58 AM EDT, 07/01/2025 (MT Newswires) -- Lululemon Athletica ( LULU ) has filed a lawsuit against Costco Wholesale ( COST ) , accusing the retailer of selling lower-priced "dupes" of its athleisure apparel.

In a complaint filed Friday in federal court in California, Lululemon alleged that Costco has "unlawfully traded" on Lululemon's reputation, goodwill and sweat equity by selling unauthorized and unlicensed products with "knockoff, infringing versions" of Lululemon designs.

"As an innovation-led company that invests significantly in the research, development, and design of our products, we take the responsibility of protecting and enforcing our intellectual property rights very seriously and pursue the appropriate legal action when necessary," a Lululemon spokesperson said in an e-mailed statement to MT Newswires Tuesday.

Lululemon is seeking monetary damages and asking the court to order Costco to stop manufacturing, marketing or selling the disputed items.

Shares of Lululemon were up more than 3% in recent trading while Costco shares were down 0.6%.

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