Zoox, a U.S.-based service to develop hardware and software for autonomous vehicles, is now part of the Amazon world.
The company is six years old and has created zero-emission, purpose-built vehicles for autonomous ride-hailing.
It has also built an autonomous "software stack" to oversee the passenger experience in the vehicle and safety on the road.
Terms of the acquisition were not disclosed but reports suggest it could be in the region of a $1 billion deal from Amazon.
Zoox has raised just over $950 million over the course of its six years in business, attracting the attention of the likes of Grok Ventures, Lux Capital, Thomas Tull and Blackbird Ventures.
The company's CEO, Aicha Evans, alongside its co-founder and chief technology officer, Jesse Levinson, will run the Zoox brand as a standalone business, Amazon says.
Evans says: "We have made great strides with our purpose-built approach to safe, autonomous mobility, and our exceptionally talented team working every day to realize that vision. We now have an even greater opportunity to realize a fully autonomous future."