The wave of mergers since the early 1990s was different from that of the 1980s, and so was the enforcement of antitrust laws. Whereas in the 1980s many mergers were among firms of unrelated industries raising few antitrust concerns, the merger wave since the early 1990s often involved the merging of cs. ompetitor, giving the combined companies the power to dominate their industries and, in theory, control prices and the availability of products. Starting from the second half of the 1990s, the enforcement of antitrust laws changed its focus from the doctrine that bigness led to power and unfair behavior to that of protecting consumers and thus refusing to approve a merger that reduced competition and was likely to increase prices to consumers (see Case Study 12-5).