Lululemon Athletica claims that Costco “unlawfully traded” on its reputation by selling unauthorized and unlicensed versions of its products.

Professor Susan Scafidi, Fashion Law Institute at Fordham School of Law, talks about why Lululemon is suing Costco, claiming “trade dress” infringement.

Lululemon Athletica Inc. is accusing Costco Wholesale Corp. of copying its apparel designs in a lawsuit — and the upscale sportswear company shared images with the court to back up its case. Here's a look at the specific products that Lululemon is calling out.