Started in Detroit just two years ago as a marketplace for second-hand sneakers, Stockx has secured $44 million from GV and Battery Ventures, with the stated purpose of expanding its business in international markets. Tech Crunch reports that the company has grown to more than $2 million in daily transactions and 800,000 users have sold or purchased items on StockX. Josh Luber, the platform's chief executive and one of its three founders, was quoted as saying that it was approaching an annual run rate of £1 billion – all in U.S. dollar transactions so far. StockX has taken off with the simple concept of providing a marketplace with sneakers that are authenticated in person, but in the last two years it has expanded into more categories, such as streetwear, handbags and watches. The funding should enable it to explore yet more product categories and perhaps open StockX stores. Luber has pointed out that the start-up actually did not need external financing but that the fundraising would help to bring fresh expertise on board. The other founders are Greg Schwartz, chief commercial officer, and Dan Gilbert, founder and chairman of Quicken Loans. The fundraising involves investors such as Karlie Kloss, the DJ Steve Aoki and the founder chairman of Salesforce, Marc Benioff.