Continuing its legal battle with those companies that make, support, and implement Linux, Microsoft this week reached a patent agreement with device maker HTC over its use of Microsoft technologies in Google Android-based smart phones. Android, of course, is built on Linux, and as with desktop and server versions of that OS, Microsoft claims that the system utilizes intellectual property owned by the software giant.

"HTC and Microsoft have a long history of technical and commercial collaboration, and today's agreement is an example of how industry leaders can reach commercial arrangements that address intellectual property," said Horacio Gutierrez, Microsoft corporate vice president and deputy general counsel. "We are pleased to continue our collaboration with HTC."

Microsoft has been pursuing Linux vendors for years and has secured numerous patent licensing agreements, protecting those companies and their customers from potentially devastating lawsuits. But this marks the first time Microsoft has gone after an Android phone maker. HTC, of course, also makes phones based on Microsoft's Windows Mobile system, and its HD2 handset is currently regarded as the apex of Windows Mobile development.

And HTC isn't the only company Microsoft has talked to recently. "We have been talking with several device manufacturers to address our concerns relative to the Android mobile platform," Gutierrez said. "Competitors do not get a free ride on our innovations."

The terms of the deal are unknown, but Microsoft says it will be receiving royalties from HTC, apparently based on sales of its Android-based phones. These phones include the Nexus One, which Google sells directly to customers from its website.

In recent days, Google has noted that the open nature of its development process was a strength that would allow it, over time, to eclipse closed phone makers such as Apple and Research in Motion (RIM). But this openness also allows Microsoft and other companies to examine the source code for its solutions. And in the case of Android, it's pretty clear that Microsoft found some infringing technologies, as it had in the past with desktop and server versions of Linux.

Other mobile companies may be a bit harder to shake down. HTC, for example, doesn't own a lot of patents because it builds hardware devices based on other companies' software designs. But handset makers such as Motorola are more formidable in this area and might be able to reach cross-licensing agreements with Microsoft in which no money changes hands. These types of agreements would protect Microsoft against similar suits from other companies related to its Windows Mobile and upcoming Windows Phone 7 systems.