The athleisure giant claims Costco's budget-friendly dupes are misleading consumers and infringing on their patents.

Lululemon is known for athleisure clothing and said that Costco uses makers of popular brands to make similar items for its ...

The athletic-wear giant in Lululemon (NASDAQ:LULU) filed suit in California last week, accusing Costco (NASDAQ:COST) of ...