Looking to earn back some of the $12.5 billion it's spending to buy Motorola Mobility, Google sent a letter to the Institute of Electrical and Electronics Engineers looking for a maximum 2.25% cut of sales for phones that use Motorola's technology, including Apple's iPhone.

The letter, which went out to the IEEE on Wednesday, outlines Google's position on Motorola patents if and when the proposed takeover is executed. (Reports say it could happen next week.) Most striking was Google's insistence on continuing to enforce a 2.25% fee on iPhones based on the model's use of Motorola patents.

Google's stance comes about two weeks after Motorola Mobility filed a lawsuit against Apple accusing the company of infringing on its technology patents. Motorola's complaint, filed in a Florida federal court, concerns patents for the iPhone 4S and Apple's iCloud service.

Patents have proved to be a key issue for Google and likely a primary impetus for the Motorola Mobility acquisition. That bid came after a very public spat this summer between Google, Apple and Microsoft over patents.

Google publicly addressed the patent issue in early August by using its Official Blog to kvetch about an "organized campaign by Oracle, Apple and other companies, waged through bogus patents." The post, by David Drummond, Google's senior vice president and chief legal officer, went on to accuse Apple and Microsoft for being "in bed together" in an attempt to hurt Google's business via patent claims.

Though Apple stayed above the fray, Microsoft General Counsel Brad Smith took to Twitter to point out that Microsoft had invited Google to jointly bid on patents from Novell. Frank X. Shaw, Microsoft's lead of corporate communications, also posted a letter from Kent Walker, Google's general counsel, refusing Microsoft's invitation regarding the Novell patents.

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