Uber has sold its entire stake in autonomous delivery robot company Serve Robotics. TechCrunch reported on Monday that Serve learned of the sale only after an official disclosure.

Uber disclosed the disposal of its entire Serve stake in a regulatory filing. The filing shows Uber has been cutting its Serve holdings since 2025 and has now sold the rest of its stake.

Even so, the final sale took Serve by surprise.

The two companies have also shown differences in their recent business direction. Serve started out in PostmatesX, the robotics unit of Postmates. Uber acquired Postmates for $2.65 billion in 2020, and the unit was spun off as Serve Robotics in 2021.

Uber invested in Serve and later entered into a business partnership in 2022. In May 2023, the companies expanded cooperation to deploy up to 2,000 Serve sidewalk delivery robots on the Uber app across multiple U.S. markets.

But Serve's second-quarter earnings release showed warning signs. Ali Kashani (알리 카샤니), Serve's co-founder and chief executive officer, said at last week's earnings release that delivery volumes through Uber rose for 17 consecutive quarters from the first quarter of 2022 through the first quarter of this year, but that trend broke in the second quarter for the first time. He cited lower-than-expected robot utilisation as the reason.

Kashani said at the Aug. 6 earnings release that the two companies held different views on a joint operating model to scale up a fleet of autonomous robots. He said they disagreed on issues such as merchant integration. He added that deliveries through other food delivery partners rose by nearly 50 percent in a single quarter over the same period.

Serve suggested it may not renew its partnership agreement with Uber when it expires in early 2027. Uber has invested in or partnered with more than 30 autonomous vehicle technology companies in recent years.