IBM - Chip IBM's overwhelming dominance in the computer market at the start of the 1970s, when it had almost 70% share, declined during the decade amid antitrust scrutiny by the Justice Department. By the late 70s, that market sharewas closer to 40%.But IBM was still a power in computing and a leading innovator, as this Super Bowl spot seeks to establish.Later Super Bowl advertising for IBM emphasized business services and a touch of humor ("Hot Seat,"2001).BRAND:IBMYEAR:1979SUPERBOWL:XIII