Motorola Mobility recently sought injunctions against Apple and Microsoft products such as iPhone, iPad, Windows and Xbox on the basis of its patents. The second case will examine whether this move amounts to an abuse of a dominant market position.
Competition Commissioner Joaquin Almunia is keen to take a stand against abuse of essential patents.
"The holders of standard-essential patents have considerable market power. This market power can be used to harm competition and I am determined to use antitrust enforcement to prevent such hold-up by patent holders," he said at a speech in Washington on Friday. Those antitrust enforcement measures include fines of up to 10 percent of a company's global turnover.
In January Almunia has opened similar proceedings against Samsung.
Google Inc, which is in the process of buying Motorola Mobility, has said it will offer Motorola patents on fair and reasonable terms once the deal is completed.
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