Here is more on this topic from wikipedia (Sorry too lazy to find a better source). Both parties (constructive insiders and those they divulge insider info to) can be convicted for insider trading:
The Dirks case also defined the concept of "constructive insiders," who are lawyers, investment bankers and others who receive confidential information from a corporation while providing services to the corporation. Constructive insiders are also liable for insider trading violations if the corporation expects the information to remain confidential, since they acquire the fiduciary duties of the true insider.
In United States v. Carpenter (1986) the U.S. Supreme Court cited an earlier ruling while unanimously upholding mail and wire fraud convictions for a defendant who received his information from a journalist rather than from the company itself. The journalist R. Foster Winans was also convicted, on the grounds that he had misappropriated information belonging to his employer, the Wall Street Journal. In that widely publicized case, Winans traded in advance of "Heard on the Street" columns appearing in the Journal.[15]
The court ruled in Carpenter: "It is well established, as a general proposition, that a person who acquires special knowledge or information by virtue of a confidential or fiduciary relationship with another is not free to exploit that knowledge or information for his own personal benefit but must account to his principle for any profits derived therefrom."
