That could give Lyft a lot more choice when deciding what car brands to buy when it begins shedding labor costs by replacing human drivers with robots.
Canada-based Magna International is one of the world's largest auto suppliers, with about $39bn in revenue, offering a wide array of products, including powertrains and car seats.
Magna will invest $200m in Lyft and collaborate on driverless system development. Lyft will lead the effort. Magna will manufacture the systems and sell them to automakers.
"Magna now becomes a one-stop shop for brands which want to deploy autonomous vehicles," said driverless vehicle industry consultant Grayson Brulte.
Last year, another major parts supplier, Delphi, bought Nutonomy, a driverless car company based in Boston, for $400m.
