The 1997 memo from Ben Waldman, at the time the head of Microsoft's Macintosh development group, to then-CEO Bill Gates, urged Mac Office 97's release. The suite, which in June 1997 had not yet reached beta, was eventually released as Office 98 in March 1998.

But Waldman understood that the next Mac Office was a stick that could be used against Apple. "The threat to cancel Mac Office 97 is certainly the strongest bargaining point we have, as doing so will do a great deal of harm to Apple immediately. I also think that Apple is taking this threat pretty seriously," Waldman said in his e-mail to Gates.

Less than six weeks after Waldman's e-mail, Microsoft and Apple announced a deal under which the former bought US$150 million of Apple stock. As part of the pact, Microsoft promised to release the next version of Office and was allowed to bundle Internet Explorer with the Mac OS. The two companies also agreed to a patent cross-licensing deal.

At the time, Apple was struggling. Steve Jobs had returned to the company only months before, and share prices were at all-time lows. The Microsoft-Apple agreement was seen by many as a bail-out of Apple by its long-time rival.

Later, the U.S. Department of Justice included the bundling of Internet Explorer among the charges it brought against Microsoft in its antitrust case. "Microsoft, by threatening to cease development of its Office for Macintosh productivity suite, coerced Apple into making Internet Explorer the default browser on all Macintosh operating systems and to disadvantage competing browsers," the federal agency charged in 1998.