Jackbox Games, Inc. (formerly Jellyvision Games, Inc.) is a Chicago-based video game developer, known for the You Don't Know Jack series (YDKJ) of trivia quiz-based video games. As a subsidiary of Jellyvision, the company was previously incorporated as Jellyvision Games, until the formal separation of the games development unit from the interactive video advertising division. The company was reincorporated as Jackbox Games in June 2013.