From DealBook:
In reversing the convictions of Anthony Chiasson and Todd Newman for trading on information received through a chain of tips, the appeals court described what was necessary to show that the original tipper had received a benefit for passing on the information, a requirement to prove this form of insider trading. ...
Although the Newman decision appears to create a “buddy exception” to insider trading, prosecutors can still pursue cases based on friendship as long as there is some evidence of a benefit that could be considered valuable. There are cases in which information is passed simply because the recipient is a friend, but often something more valuable is exchanged when confidential information is doled out secretly. ...
The United States Court of Appeals for the Second Circuit has made proving insider trading more difficult in tipping cases but did not erect an insurmountable hurdle.
Go read the whole thing.