As one legal tussle follows another, so the various ins and outs of patent law in the mobile field seems to get more and more complex.

Indeed, you'd be hard pressed to find a major OEM without some kind of patent case on its books, with the latest episode of courtroom drama coming from Motorola.

The firm was reportedly been given the green light by its soon-to-be parent company Google to take on Apple over its alleged use of Motorola patents in both iPhone 4S and iCloud.

Two's company

The case - opened in the Southern District of Florida - refers to a total six patents previously debated by the same court. All six are focused on iPhone 4S, with two of them making reference to iCloud.

It's a chapter in Apple's recent tussles in Android OEMs that IP expert Florian Mueller claims couldn't have happened without Google's go-ahead.

"Google must have authorised this action, because this complaint formally represents a new lawsuit and Section 5.01(j) of the Google-Motorola merger agreement does not allow MMI to 'assert any Intellectual Property Right in any new Action' without Google's consent," he points out on Foss Patents.

"It's certainly not the same kind of aggressive escalation as a lawsuit over a new set of patents would have been, but this shows that Motorola continues to fight hard.

"The fact that Google signs off on an additional lawsuit at this stage - as opposed to waiting for its purchase of MMI to close - also says something."

[source: Foss Patents]