The warehouse giant is accused of leading customers to believe some of their products are made by the same manufacturers as the high-end retailer.

Dupes are a common phenomenon in fashion, but they have risen in popularity in recent years thanks to social media influencers. Costco carries men’s, women’s and children’s clothing, including activewear such as yoga jackets, leggings and joggers.

Lululemon said in a lawsuit filed on Friday, June 27, that Costco “unlawfully traded” on the athleisure brand’s “reputation, goodwill and sweat equity by selling unauthorized and unlicensed apparel employing knockoff, infringing versions” of its products, according to CNN.