Alphabet Inc (NASDAQ:$GOOGL) has officially invested in rise-hailing startup Lyft.

The official announcement that CapitalG, Alphabet’s investment fund, is leading a $1 billion financing round for Lyft came on Thursday. The move follows an agreement made in May between Lyft and Alphabet’s self-driving subsidiary Waymo to work together on the development of autonomous-vehicle technology.

Alphabet hasn’t been the only interested party, though. Several automakers and tech companies are working on self-driving technology of their own — including General Motors (NYSE:$GM), which made a huge investment in Lyft last year.

It’s a big move, especially considering that Waymo is locked in a fierce legal battle with Lyft arch-rival Uber Technologies. Waymo has alleged that a former employee stole key technology secrets related to self-driving when he left to form a new company; that company was acquired by Uber a few months later.

Waymo also has its eyes set on dominating the market for autonomous-vehicle systems, an emerging industry with large growth and profit potential. Ride-hailing is expected to be an important early market for self-driving vehicles, and Lyft could be a major customer.

Additionally, since last month, Lyft has been taking steps toward an initial public offering in 2018.

Featured Image: twitter