After the tax avoidance issue, Apple is again on the world spotlight as EU antitrust regulators investigate iPhone sales tactics in the region. Authorities are seeking more information about the alleged distribution deals negotiated by Apple among mobile telecommunication providers. The reported deals were meant to intentionally shut down rival smartphone manufacturers.

According to Reuters, the European Commission sent questionnaire to mobile telecom operators to obtain the much needed information. The Commission earlier declared that such behavior between Apple and telecom companies is a possible violation of EU antitrust regulations.

Mobile telecom companies filed complaints against Apple last year regarding marketing of the company's smartphones and tablets, and handset subsidies. The surveys are part of regular procedure for antitrust cases. Survey information will help the Commission decide whether to reject complaints or open a case against the alleged violator.

The questionnaire informs mobile telecom companies that the Commission has information about Apple and the networks engaging in distribution negotiations. These actions may exclude other smartphone manufacturers from the market.

Using the survey, the Commission wanted to ask telecom operators if they were obliged or coerced by Apple to purchase a minimum number of iPhones and market iPhones differently than rival smartphone brands. The Commission also inquired about the alleged handset subsidies Apple ensures to mobile telecom companies if they give the same if not better terms for Apple products.

Smartphone manufacturers like Apple usually get large subsidies from U.S. and European mobile operators. Consumers benefit from discounts on their preferred device in exchange for signing on a wireless contract lasting up to two years.

Antitrust regulators would also like to verify the information about the iPhone 5 restriction on LTE networks. Apple reportedly prohibits companies to use its latest flagship phone for LTE network connections. The Commission gives mobile telecoms until June 17 to submit their replies.