Back to the 1970s: IBM in mainframe antitrust suit again

International Business Machines (IBM) used to dominate the computer industry -- especially in the 1960s when mainframe computers were the only game in town. During the 1970s, that dominance gave birth to a lengthy antitrust lawsuit, which Ronald Reagan's justice department dismissed in 1982. Some 27 years later, Big Blue's mainframe business is in antitrust hot water again.

The antitrust laws are a uniquely American institution. They came into being in the 1890s with the Sherman Act, which prohibits the exercise of monopoly power. That's when a company that dominates its industry uses its power to keep out competitors. Antitrust laws pit the interests of small companies against those of big ones. And somewhere in there is the desire to protect consumers by giving them competitive markets, which are supposed to push down prices and boost quality.