You will read  that the United States Supreme Court unanimously re-established the “old rule” for liability for insider trading: if person A tips person B with material inside information, both parties will be liable for insider trading under the securities laws. This should not be analytically startlingly and, indeed, the Supreme Court had no trouble with it; how often do you see an unanimous decision? But the importance of this decision is that it overturns a cryptic 2014 case decided by the Federal Second Circuit (New York), which held that the government had to prove that the tipper and the tippee “needed to know that insiders . . . were improperly leaking confidential information in exchange for some personal benefit.” Justice Alito made analysis far simpler, removing the test of trying to measure the presence of personal benefit to the tipper: “[Tipper] would have breached his duty had he personally traded on the information here himself and then given the proceeds as a gift to[Tippee]. It is obvious that [Tipper] would personally benefit in that situation. But [Tipper] effectively achieved the same result by disclosing the information to [Tippee], and allowing him to trade on it.” The practical effect of this decision is significant, particularly as it comes from the Supreme Court so it is not likely to be messed with by a trial judge who is charging a jury. Practically speaking, if somebody has a relationship with another person which is sufficiently close as to induce the passing of inside information, both parties are going to have liability.