There are two questions here. One, why is an American firm asking European regulators to investigate another American firm? And two, does Microsoft have a case here?
The first one's easy. As Microsoft knows all too well, European regulators tend to take a tougher line than US ones: for example it was EU, not US, regulators who forced Microsoft to offer a ballot screen of different Windows browsers, and it was EU, not US, regulators who fined Microsoft huge amounts of cash and ordered it to play nice with other networking software.
The second one depends on whether Microsoft's telling the truth. If it is, then Google's behaving in much the same way Microsoft behaved before the EU got involved. Microsoft isn't just saying that Google is too big in search, although in Europe it is, its near-100% market share meaning that when Europeans search, they Google.
Microsoft is saying that Google's playing dirty.
Google has long argued that competition is simple: if someone makes a better search engine, people will dump Google and flock to it. But what if Google could break the internet in such a way that you couldn't make a better search engine? What if Google could access data that other search engines couldn't?
According to Microsoft, that's exactly what Google's doing.
Google isn't just a search engine. It's an enormous content provider, too. Just look at YouTube, or the books Google has been merrily scanning. According to Microsoft, Google gets better access to that content than anybody else. "It has put a growing number of technical measures to restrict competing search engines from properly accessing it for their search results," Microsoft says.
Microsoft also claims that Google gives preferential treatment to its pals. Android and iPhones get full access to YouTube's features; Windows Phone doesn't. Microsoft says it's got the app, but it can't release it without Google's permission - "permission Google has refused to provide."
Does that sound like Google? The open, fair dealing Google? Nope. But it does sound awfully like this Google, the one BusinessWeek says is getting awfully strict about its supposedly open Honeycomb OS. You want Honeycomb? You'd better play by Google's rules, and that means no Bing and no features Google disapproves of.
Microsoft, then, is accusing Google of doing a Microsoft, of rigging the game so that Google always wins. Maybe that's unfair, and maybe the allegations are entirely without merit. But I doubt it. As every playground philosopher knows, it takes one to know one - and if anyone knows what constitutes anti-competitive behaviour, it's Microsoft.
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Writer, broadcaster, musician and kitchen gadget obsessive Carrie Marshall (Twitter) has been writing about tech since 1998, contributing sage advice and odd opinions to all kinds of magazines and websites as well as writing more than a dozen books. Her memoir, Carrie Kills A Man, is on sale now. She is the singer in Glaswegian rock band HAVR.