If you trust Wikipedia, this is the first sentence in the US section on insider trading: "Until the 21st century and the European Union's market abuse laws, the United States was the leading country in prohibiting insider trading made on the basis of material non-public information."[0]

I'm not a lawyer, nor do I work in finance, but I think the key is what exactly constitutes "non-public information." I can trade on all the public information regarding Tesla's cars, like reviews, published production numbers, and Elon's tweets and my own analysis of all tat but not on the word of a someone who works there saying they've got some big unexpected news.

There's a bunch of interesting cases about whats on the edge, for example, commercial satellite imagery to count cars in parking lots[1].

[0]: https://en.wikipedia.org/wiki/Insider_trading#United_States_...

[1]: https://www.theatlantic.com/magazine/archive/2019/05/stock-v...