Today, the Clark Bar uses its original formula pioneered by Irish immigrant David L. Clark in Pittsburgh, Pennsylvania in 1886. It comes in milk and dark chocolate varieties. It was acquired by Beatrice Foods in 1955 then Leaf in 1983, and in late 1990 studied consolidating operations in Chicago before the Pittsburgh area managed to retain the brand with the firm moving from the Chicago O'Hare suburb to the northside of Pittsburgh in the fall of 1991. It became independent again with headquarters retained in Pittsburgh in 1996 when Hershey acquired Leaf's North American operations. NECCO bought it in 1999.