Facebook made news at the start of the year when it announced that it's acquiring WhatsApp. The deal has so far gone through the usual motions, but the social network can't completely wrap up its purchase of the mobile messaging app without the approval of regulators from the European Union.

To help it decide the fate of the Facebook-WhatsApp deal, antitrust regulators in the EU have turned to competitors for the two companies, asking if the $19-billion bid the social network made will cause price increases and lead to stunting in innovation.

The deal is the largest that Facebook has ever made. Many are saying that it's far too pricey for WhatsApp, but the move will definitely give the social network a stronger presence in the market for mobile messaging which has been growing steadily and exponentially.

To facilitate their query, EU regulators sent out questionnaires to third parties. In these, recipients were given a series of questions and were asked to rate the deal as having a positive, neutral, or negative impact on customers and users of social networks and mobile messaging apps. Those who think that the deal would have a negative impact were also requested to expound on their answer by giving concrete examples of the effects they had in mind.

EU regulators also wanted to determine if WhatsApp's services may be used as an alternative to traditional text messages, voice calls, and emails. The welfare of Facebook advertisers was also considered because regulators want to know if advertisers would still have the option to change their advertisements should the deal cause an increase in price in the market. Regulators are also keen on knowing what potential problems will arise for competitors for the two companies if the deal is finalized.

Examples of questions regulators are asking include: "As a result of the Facebook/WhatsApp transaction, do you expect users of WhatsApp to face greater difficulties in switching to another consumer communications service/app?" and "As a result of the Facebook/WhatsApp transaction, do you expect that it will be more difficult for WhatsApp's competitors to expand their user base or to launch a new consumer communications service/app in the European Economic Area?"

U.S. regulators have already cleared the deal in April so EU's approval is the last piece of the puzzle Facebook wants in place to complete its acquisition of WhatsApp. The social network is expecting to have everything finalized this year.