Google is in familiar territory after it again attracted the attention of the Federal Trade Commission (FTC) which is carrying out an antitrust investigation into its $1 billion-plus acquistion of Israel-based social maps startup Waze.

Google confirmed to the Wall Street Journal that it has been contacted by the FTC about the report — initially flagged by the New York Post — but it declined to provide further details. The FTC did not provide comment to the newspaper.

The probe is understood to center around Google’s intentions for buying Waze, and how the deal will impact competition in the mapping market worldwide.

A recent FTC investigation into Google’s search practices ended in January 2013, drawing criticism from Microsoft for its leniency. More recently, the organization began probing Google’s graphical-ad business — so it’s fair to say the two parties are already well acquainted.

Google pledged that Waze will be run independently as its own company. Google plans to add Waze’s traffic monitoring to its own maps, and give the Israeli firm broader access to Google mapping technologies — however the Journal claims the FTC may request that those plans remain on hold until its report is complete.

Waze has nearly 50 million registered users and, though its revenue is too small to automatically trigger an antitrust probe, the FTC is said to have taken an interest in the deal after it closed this month.

Speculation about the sale of Waze had been ongoing for months with the company attracting the attention of the some of the world’s most recognizable tech firms. Waze was first linked to a deal with Apple, then Facebook was reportedly unsuccessful with a bid — apparently due to its preference to relocate the firm to the US. Added to that, Microsoft is an investor in the startup.

The deal was seen by many as as defensive move from Google that prevented Waze and its technology ending up in the hands of a rival like Facebook or Apple. That’s an angle that is sure to interest the FTC.

Equally though, Google can make a valid claim that Waze adds a social layer to its mapping service and incorporates new technology for identifying road traffic and serving drivers convenient routes. Furthermore, it appears to be a fit with Google’s social plans and an integration with Google+ in the future seems plausible should Google wish to tighten its links with the Waze service.

Image credit: Thinkstock

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