The European Commission has asked Samsung and Apple to turn over data related to the enforcement of mobile-related patents.
"I can confirm that the Commission has indeed sent requests for information to Apple and Samsung concerning the enforcement of standards-essential patents in the mobile telephony sector," a commission spokeswoman said in an email. "Such requests for information are standard procedure in antitrust investigations to allow the Commission to establish the relevant facts in a case."
The issue made headlines after Apple announced the investigation in a recent court filing.
"Samsung's litigation campaign and other conduct related to its Declared-Essential Patents is so egregious that the European Commission recently has opened an investigation to determine whether Samsung's behavior violates EU competition law," the filing said.
When asked about the details of the case, the EU spokeswoman said the commission had "no other comments at this stage."
In a statement, Samsung said it "has at all times remained committed to fair, reasonable and non-discriminatory licensing terms for our wireless standards-related patents. We have received a request for information from the Commission and are cooperating fully. Note that this is a preliminary investigation and the European Commission has not yet determined whether to conduct a full investigation."
Patent expert Florian Mueller said in a blog post that the investigation is related to "Samsung's various attempts to shut down Apple products—most recently the iPhone 4S—with patents declared essential to the 3G industry standard."
According to Mueller, the EU investigation is the "most important development to date related to the world-spanning dispute between these two companies" because it could force Samsung to withdraw its claims against Apple.
At issue is something known as FRAND (fair, reasonable and non-discriminatory) licensing obligations, which are intended to keep major corporations in check and avoid abusive patent-related behavior.
"In my view, FRAND patent holders can ask for reasonable compensation, but they are not allowed to overcharge or to shut down products as long as an alleged infringer is willing to take a license on FRAND terms (if there actually is an infringement of valid patents)," Mueller wrote.
Last month, a Dutch court denied Samsung's request to ban Apple mobile products from the Netherlands. A judge at the district court in the Hague ruled that Samsung's 3G patents were "essential" patents for any mobile device running 3G, and therefore cannot be used as a reason for banning an infringing party's cell phones.
Meanwhile, Mueller speculated that despite the request for information from Apple, Samsung is the real target. "I can say definitively that neither the Commission's statement nor Samsung's reaction nor Apple's court filing provide any reasonable indication that Apple's own behavior is being probed," he wrote.
The larger patent battle between Samsung and Apple kicked off in April, when Apple sued Samsung for copying the look and feel of its iPhone and iPad in its flagship Galaxy S line of devices. The battle has since expanded to about two dozen countries. Apple has already succeeded in getting the Galaxy Tab 10.1 temporarily banned in Germany and Australia. Samsung is also trying to get the iPhone 4S banned in several countries but was recently shot down in Italy.
Editor's Note: This story was updated at 1pm Eastern with comment from Samsung.