In a lawsuit filed Friday, Lululemon claimed Costco was violating its patents by selling “knockoff” versions of its pants, hoodies and jackets.

Lululemon is suing Costco, alleging that the discount wholesaler is selling knockoffs of its $128 pants and other pricey athleisure clothing.

Costco is one of the most popular retailers in the U.S. As of May 26, 2025, there are 628 Costco stores in the United States, ...