Misappropriation theory is the following: > The misappropriation theory of insider trading is a form of insider trading where an individual trades stock in a corporation, with whom they are unaffiliated, on the basis of material non-public information they obtained through a breach of a fiduciary duty owed to the source of the information
The important part, which you're right was unclear in my comment is that the recipient of the information must have a fiduciary relationship with the source of the information, even if they do not have one with the company in question at all. That's the distinction.