Former Roblox headquarters, now occupied by Guidewire Software. Roblox Corporation (/ ˈ r oʊ b l ɒ k s / ROH-bloks) is an American video game developer based in San Mateo, California. Founded in 2004 by David Baszucki and Erik Cassel, the company is the developer of Roblox, which was released in 2006.