European Union regulators are looking into whether mobile phone operators who block customers from making inexpensive wireless calls over the Internet are breaking competition rules.
The European Commission, the EU antitrust authority, has sent questionnaires to phone companies asking what "tools" they use to "control, manage, block, slow down or otherwise restrict or filter" Internet-based voice calls.
The EU deadline for responding to the survey was Tuesday. The questionnaire, obtained by Bloomberg News, does not identify any companies.
Some mobile carriers have blocked services that use voice-over-Internet protocol, or VoIP, which allows users to make calls over the Web. Companies may be seeking to stop customers from accessing applications, like eBay's Skype, to defend voice revenue from the less expensive Internet services, Carolina Milanesi, research director for mobile devices at Gartner, the research company, said.