The Unites States International Trade Commission held today that Motorola's Android products infringe four claims of a Microsoft patent — the ruling is an "initial final determination" by an administrative law judge, which can still be reviewed by the full Commission. The infringement finding could implicate well over a dozen Motorola devices, including the Razr, Atrix, Bravo, Charm, Xoom tablet, and several Droid models. The news comes on the heels of yesterday's ITC ruling imposing a ban on all HTC Android devices effective April 2012, and after months of Microsoft negotiating patent licenses with every other major Android OEM.

Here's the statement Microsoft just sent us:

We are pleased with the ITC's initial determination finding Motorola violated four claims of a Microsoft patent. As Samsung, HTC, Acer and other companies have recognized, respecting others' intellectual property through licensing is the right path forward.

The primary debate here is apparently about US Patent No. 6,370,566, which allows users to "schedule an appointment anytime, anywhere, and invite others to attend, making easy use of email addresses and contact information and synchronizing calendars across their phone, PC and other devices," according to a Microsoft representative.

Update: Motorola just gave us its official statement on the ITC ruling, saying that it's "very pleased that the majority of the rulings were favorable to Motorola Mobility" and that the "initial determination may provide clarity on the definition of the Microsoft '566 patent for which a violation was found and will help us avoid infringement of this patent in the U.S. market."

That tracks right along with HTC's reaction to yesterday's final ITC ruling where its Android-based devices were found to infringe a single Apple patent. It's a significant victory for Motorola to get a favorable ruling on a majority of the infringement claims brought against it, but as the HTC situation demonstrates, even a single finding of infringement can result in an injunction. The ultimate consumer impact will depend mostly on how easy, or realistic, it is for Motorola to design around or eliminate the technology covered by that remaining patent. And, of course, this initial determination by the ITC is still subject to review by the full Commission, so we'll just have to wait a bit longer to weigh the real ramifications of this decision.

Matt Macari contributed to this report.