Cheaper look-alikes have been around for years, but social media has made them more popular. Dupes can move into shaky legal territory if concerns arise around consumer confusion or patented designs.

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

In a 49-page lawsuit filed in California, Lululemon accused the retail wholesaler of selling knockoff versions of its Scuba clothing and popular ABC men’s pants.