Apple’s strategy of a “walled garden” now seems to be inspected by U.S. antitrust authorities. The Wall Street Journal reports that the Federal Trade Commission and the Justice Department are overhauling Apple’s latest license change for the iPhone OS SDK 4.0. Although the process is at a preliminary stage, the interest of antitrust authorities show how powerful Apple has become in the field of mobile computing.

Some critics contend Apple is now engaging in the kind of tactics that got Microsoft Corp. in trouble with antitrust enforcers in the 1990s. “Apple is playing right out of Microsoft’s playbook—and it’s one they complained about a lot,” said David Balto, a former FTC official now at the Center for American Progress, a left-leaning think tank.

Apple could try to head off trouble with antitrust enforcers by changing the terms of its developer agreement, one person familiar with the situation said.

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