Marco della Cava

USA TODAY

SAN FRANCISCO — Uber admitted it used a tool to thwart city regulators in a statement Wednesday that announced a review of its controversial Greyball technology.

Greyballing, a play on blackballing, was a way for Uber officials to remotely provide ghost driver information to a targeted individual. A March 3 report on the program in The New York Times cited a 2014 example where a regulator in Portland, Ore., a city in which Uber was operating without approval at the time, was unable to hail a car because of his Greyball-powered app.

"We have started a review of the different ways this technology has been used to date," Joe Sullivan, Uber's chief security officer, wrote in a blog post. "In addition, we are expressly prohibiting its use to target action by local regulators going forward."

Sullivan added that it would take the company "some time" to change configurations on Greyball. He also suggested that a range of organizations had requested more information on Greyball's use, and "we will be working to respond to their inquiries once we have finished our review."

Portland mayor Ted Wheeler told the Times that he was "very concerned" about Greyball's use to prevent city regulators from doing their job in overseeing Uber's operations.

Uber's response to the Times was that Greyball, which its legal team had approved, was created in order to deny ride requests to users who were violating the company's terms of service.

The ride-hailing giant's post reiterated that stance in the post, adding that Greyball has "been used for many purposes, for example: the testing of new features by employees; marketing promotions; fraud prevention; to protect our partners from physical harm."

Greyball's retooling comes at a time of great challenge for the $70 billion private company, which until recently has enjoyed a meteoric rise.

In the past few months, it has been hit with a #DeleteUber social media campaign in reaction to its initial stance on President Trump's immigration ban, charges of rampant sexism from a former employee and a lawsuit from Alphabet-owned Waymo over self-driving car sensor technology.

What's more, CEO Travis Kalanick, who has faced down an upset staff and a video that showed him berating an Uber driver, recently announced he would be seeking help with his leadership style and is in search of a chief operating officer.

Follow USA TODAY tech reporter Marco della Cava on Twitter.

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