Only if the information is acquired from an insider. If you develop exclusive information without relying on internal sources, it's not insider trading. But that is very hard to do.

I'm convinced that some amount of insider trading is going on. Just the other day I was in a sauna at a gym in midtown and walked in on some bankers discussing a deal they were working on and literally whether they ought to illegal trade on their insider knowledge. They kept on talking about it for a time while I was with them, and then said of me, "Better hope this guy's not from the SEC!" It was pretty blatant.

Now these kids were idiots, so maybe they wouldn't even be able to make a profit with insider knowledge. But if they're talking about it, I'm sure non-zero numbers of people are doing it.

That's common confusion.

If you work at Wal-Mart, know the financials of store sales before it is released, and trade off that, you can go to jail.

But you don't work at Wal-Mart, buy satellite imagery and count cars in the parking lots to estimate sales, and trade off that, then it's totally cool.

It's not so much that the information is non-public that makes it a crime - it's the insiderness - abusing a position of investor's trust.

Not legal advice, but it seems to be only if someone with a duty to keep something secret revealed it. It's fine to figure it out another way. (Satellite pictures, visiting stores, etc.)