Elon Musk’s latest blending of business interests puts his Grok AI chatbot in Teslas—and raises questions around data and privacy

This week, owners of Tesla cars learned that they were getting a freebie: Starting July 12, all new Tesla vehicles have automatically had the Grok AI chatbot installed and available to use.

Grok, of course, is the chatbot created by xAI, the privately-held AI company launched two years ago by Tesla CEO Elon Musk. Like a gas station offering a free car wash with a fill-up, Musk appears to be leveraging his various assets and business endeavors to give customers extra value. In this case...