There you have it. This story is now confirmed.
"Uber is officially exiting Southeast Asia, selling its regional business to its primary competitor, Grab. As part of the deal, Uber gets a 27.5 percent stake in Grab, which was last valued at $6 billion. This is the third major market Uber has exited like this: In August 2016, China-based ride-hail behemoth Didi acquired Uber’s business in the country.; in July 2017, Uber pulled its operations out of Russia by merging with competitor Yandex Taxi."