In the clearest case, insider trading laws kick in when you bribe an insider for information. Acting on something you overhead, hiring a private investigator t

In the clearest case, insider trading laws kick in when you bribe an insider for information. Acting on something you overhead, hiring a private investigator to see who's having lunch with who, etc, are all fair game; paying for an advantage in the market is not. It turns out to be way more complicated in practice though. It looks like the SEC just settles things on a case-by-case basis.