Lululemon has filed a lawsuit against Costco that accuses the wholesale club operator of selling lower-priced duplicates of some of its popular athleisure clothing. Lululemon Athletica claims in

Lululemon is suing Costco, alleging the wholesale retailer knowingly sold knockoff versions or dupes of its popular products.

Dupes, or less expensive alternatives to luxury products, are far from new, but their popularity has surged with social media trends.