Fashion "dupes," or less expensive versions of high-end clothing and other accessories, are just about everywhere these days. They're also drawing some businesses into legal battles.

Lululemon alleges that Costco has stolen the intellectual property of its Scuba hoodies and sweatshirts, Define jackets and ABC pants.

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