Motorola has won a ruling against Microsoft that may result in blocking imports of the Xbox 360 to the US. An International Trade Commission judge found that Microsoft was violating four of five Motorola Mobility patents. If the finding is approved by a six-member commission, it can ban the import of goods that violate US patents.

An outright ban is unlikely, but it does give Motorola leverage against Microsoft. Bloomberg reports that it can use this leverage to reach a settlement, if Microsoft wants to assure it avoids the red tape. The patents include two for video decoding, two for WiFi technology, and one that establishes communication between the console and accessories. The judge ruled that the second WiFi patent wasn't infringed, and one of the video-coding patents was invalid.

Motorola's patent claim was in retaliation for Microsoft lodging its own patent-infringement charge against Motorola phones that run Android. A separate judge found that Motorola had infringed on one of seven Microsoft patents. Motorola initially sent a letter demanding a 2.25 percent royalty on the end price of products including the Xbox.

The commission plans to complete the investigation into the Microsoft infringement by August 23; first will come the determination of the Motorola infringement, as a decision is due May 18.

"Microsoft continues to infringe Motorola Mobility's patent portfolio, and we remain confident in our position," said a Motorola spokesperson in a statement. "This case was filed in response to Microsoft's litigate-first patent attack strategy, and we look forward to the full commission's ruling in August."

In its own statement, a Microsoft representative said, "Today's recommendation by the administrative law judge is the first step in the process leading to the commission's final ruling. We remain confident the commission will ultimately rule in Microsoft's favor in this case and that Motorola will be held to its promise to make its standard-essential patents available on fair and reasonable terms."