Founded in 1951, Jack in the Box is one of the largest hamburger chains in the United States. It is a restaurant company that operates and franchises restaurants under the Jack in the Box brand names. The company operates more than 2,170 quick-serve restaurants in over 15 U.S. states. Additionally, through a wholly owned subsidiary, Jack in the Box also operates and franchises more than 470 casual dining restaurants under the Qdoba Mexican Grill brand name in over 40 U.S. states and the District of Columbia. In addition, the company operates a proprietary chain of more than 60 convenience stores under the Quick Stuff brand name. Jack in the Box offers a range of hamburgers, specialty sandwiches, salads and ice-cream shakes. It serves hamburgers under the Jumbo Jack and Sourdough Jack brand names.