Uber is facing a criminal investigation in the US following revelations over its use of secretive 'Greyball' software, which the company used to mine customer data for sensitive information.
Reuters reports that the Department of Justice (DoJ) has launched an investigation into the software, which it also used to help it evade law enforcement.
First uncovered in March, Greyball enabled Uber to use information such as geolocation data, credit card details and social media accounts to identify government officials, and then force through a fake version of the Uber app when they tried to book a ride.
This app would show them cars within the app navigating nearby, but no one would come pick them up.
The tool was said to be widely used in areas where Uber services were restricted, banned or not yet approved, including Portland, Oregon, Philadelphia, Boston, and Las Vegas, as well as France, Australia, China, South Korea and Italy.
Uber declined to comment on Reuters' report, but has previously defended its use of the software, saying it "denies ride requests to fraudulent users who are violating our terms of service - whether that's people aiming to physically harm drivers, competitors looking to disrupt our operations, or opponents who collude with officials on secret ‘stings' meant to entrap drivers".
In a letter sent last week to transport regulators in Portland, however, Uber said it only used the greyball software "exceedingly sparingly" and had not used it since April 2015 when it was granted permission to operate in the area.
The report doesn't specify what laws may have been broken, but does say that Greyball may have violated Uber's own terms of service by mining users' credit card and social media data.
A separate report in the Wall Street Journal suggested that the investigation was focused on how Uber used the Greyball software, and added that a federal grand jury had subpoenaed Greyball records from Uber.
The DoJ's investigation is reportedly in its "early stages", and it remains unclear what sanctions Uber will face if it is found that did act illegally.
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