Is Microsoft Allowing Ubuntu Linux on Azure without a Patent Deal?

From the ‘Ethical Concerns’ files:

Microsoft alleged years ago that Linux and Open Source technologies infringe on over 200 Microsoft patents. It’s that basic allegation that Microsoft used to convince Novell/SUSE to sign a a Patent deal and it’s the same basic underpinning for a dozen deals with Android vendors.

So why is Microsoft allowing Linux to run on its Azure cloud? In particular, why Ubuntu?

Perhaps there is some kind of hidden deal. It’s a question I asked Canonical directly