StockX, the online reseller of sneakers and other cult products, has raised an additional $275 million in a Series E funding round that values the Detroit-based company at $2.8 billion. StockX says its sales were up by 75 percent to more than $100 million in the third quarter, leading to company to achieve break-even results. In addition to one of its existing shareholders, Tiger Global Management, new participants in the round include Altimiter Capital, Sands Capital and Whale Rock Capital. StockX started four years ago as a marketplace for sneaker collectibles. It recently expanded into streetwear, accessories and other collectibles including video games such as the newly released Xbox Series X and the Playstation 5.