Google yesterday asked the U.S. International Trade Commission (USITC) to block the testimony of a Microsoft expert witness in the latter's 10-month-old action against Motorola over patents allegedly used by Android.

In a motion filed with the ITC Wednesday, Google asked that Robert Stevenson, an expert hired by Microsoft, be barred from testifying about the Android source code at an upcoming hearing because Microsoft violated a confidentiality agreement struck between Microsoft, Motorola and Google.

According to Google, Microsoft did not ask permission before showing Stevenson the Android source code.

"The protective order governing confidentiality in this investigation explicitly requires that Microsoft disclose to Google any consultant or expert seeking access to Google confidential business information or highly confidential source code before [emphasis in original] allowing a consultant or expert to review such information so that Google has an opportunity to object prior to disclosure," read Google's complaint.

A protective order in the case restricts access to the Android source code, limiting the number of people who can review the code and requiring that Microsoft and Motorola "give prior written notice" to Google before showing the source code to a technical advisor. Google is to have 10 days to object.

Microsoft did not do that, Google alleged, as it moved to prevent Stevenson from testifying at the evidentiary hearing slated for later this month.

"The confidential source code improperly provided to Dr. Stevenson is highly proprietary source code that Google does not even share with its partners, such as Motorola," Google said.

Microsoft submitted its complaint against Motorola with the ITC last October -- and filed a lawsuit in federal court at the same time -- charging the smartphone maker with violating several Microsoft patents in its Android devices.

"We have a responsibility to our customers, partners, and shareholders to safeguard the billions of dollars we invest each year in bringing innovative software products and services to market," said Horacio Gutierrez, a Microsoft deputy general counsel, in a statement Oct. 1, 2010. "Motorola needs to stop its infringement of our patented inventions in its Android smartphones."

Yesterday's move by Google was little more than delaying tactic, said patent activist and analyst Florian Mueller today. Mueller writes the FOSS Patents blog, where he regularly posts analyses of the ongoing patent wars.

"This is a secondary theater of war," said Mueller in an email interview. "It's about procedural tactics, maybe hoping that this could cause a delay, but whatever the outcome may be, it won't change anything about the substance of this case."

He has a point: Microsoft was granted permission to show the Android source code to others besides Stevenson, according to Google's motion before the ITC, so it will not be bereft of expert testimony.

Mueller also noted that Google's motion was filed by the same law firm that also represents Motorola in the case with Microsoft, and defends Samsung, Motorola and HTC in those companies patent battles with Apple.

Google's filing was submitted by lawyers at Quinn Emanuel Urquhart & Sullivan's Los Angeles and San Francisco offices.

"It was always known that Quinn Emanuel was close to Google, and it was hardly a coincidence that all those Android device makers turned to that firm," said Mueller. "But the fact that they make a filing on Google's behalf here -- though they also represent Motorola in the same investigation -- is interesting. The latest motion is a more direct kind of intervention than anything they previously did on Google's behalf."

Earlier this month, Google's chief legal officer accused Microsoft, Apple and Oracle of waging a "hostile, organized campaign against Android" using patent claims, and promised it would stop "those who are trying to strangle it."

Mueller didn't give Motorola much of a chance in the Microsoft patent challenge, and believes the ITC action presents Google and Android with its toughest test.

"I think Google is extremely afraid of the outcome of this particular ITC investigation," said Mueller. "All of the infringement assertions that Microsoft brought relate to the Android codebase. If this investigation finds Motorola and, in fact, all Android devices to infringe various valid Microsoft patents, all of Google's hardware partners will have to pay royalties to Microsoft."

Several Android handset makers already pay Microsoft licensing royalties, including HTC and several lesser-known companies.

Microsoft today declined to comment on Google's motion before the ITC.

Gregg Keizer covers Microsoft, security issues, Apple, Web browsers and general technology breaking news for Computerworld. Follow Gregg on Twitter at @gkeizer, on Google+ or subscribe to Gregg's RSS feed . His e-mail address is gkeizer@computerworld.com.

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