For Google, Amazon, Facebook and many other tech companies, 2016 has seen a major focus on artificial intelligence. Google just recently announced a more conversational Assistant, while Amazon’s Alexa voice service is constantly getting more connected thanks to the help of third-party developers. As this technology keeps growing, though, it wouldn’t be too farfetched to be a little nervous for the future.

Speaking at Recode‘s Code Conference 2016, Tesla and SpaceX founder Elon Musk sat down with Walt Mossberg and Kara Swisher to talk about what’s to come of AI. Mossberg asked Musk whether or not he’s worried about the efforts of major companies like Google and Facebook when it comes to AI advancements. “I wouldn’t name a name,” said Musk, staring at the floor, “but there’s only one.” Mossberg then tried to pry the specific company name out of the Tesla CEO, but he wouldn’t budge. “There’s only one,” Musk said.

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Is Google the company that has Musk nervous? What about Facebook? Since the Tesla founder refused to spill the beans, the answer will have to remain a mystery for now.

If you have time, you should definitely give the full interview a watch. Below I’ve attached the AI talk, but you can also find more snippets on Recode’s YouTube channel.

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