How is This Not an Antitrust Violation?

At a recent Linux event a top Microsoft exec in charge of platform strategy was recorded as saying that Microsoft would not be releasing a version of MS Office for Linux. This of course solicited the standard response from the FOSS community that we don't need Microsoft to make a top-notch productivity suite and that we're better off without them. I'm not so sure about that, but I have a different beef with the comment. As usual, a quote is illustrative

Microsoft is 100 percent focused on Windows: We have invested billions of dollars in it. We have created Office for the Mac but--and I thought I had been clear on this already when I said 'No'--we have no plans at this time to build Office on Linux

Seems like the standard line you would expect from a platform strategist, it being strategic and all.

The problem is that Microsoft is a known monopolist. There is no legal question about that, and thus is held to a higher standard under out antitrust laws. One of those standards is that it cannot use its monopoly status to maintain its monopoly. Under US law its not bad to be a monoploy, only bad to act like a monoploy. When Microsoft turns down an opportunity to expand the MS Office install base into the Linux world because it wants to shore up support for Windows, that is using its monoploy power to sustain an existing monopoly. No reasonable industry competitor should turn down an opportunity to expand into a growing market, and our laws are in place to ensure that the improper incentives of industry consolidation and predatory pricing don't get in the way of serving consumers and fostering competition. The only remaining question for me is whether the Federal Trade Commission or the DOJ will actually enforce the law?