Bull was founded in 1931, as H.W. Egli - Bull, to capitalize on the punched card technology patents of Norwegian engineer Fredrik Rosing Bull.
The company has also been known at various times as Bull General Electric, Honeywell Bull, CII Honeywell Bull, and Bull HN.
The company has undergone many takeovers and mergers since its formation. In particular, it has had various ownership relations with General Electric, Honeywell, and NEC from the 1960s to the 1980s; and with Motorola, Debeka, and France Télécom more recently. It acquired Honeywell Information Systems in the late 1980s, and later also had a share of Zenith Data Systems and Packard Bell.
In 2014 Bull was acquired by Atos.