"For decades, the SEC has kept the insider-trading rules vague and undefined. This ambiguity increases the SEC's power and allows government lawyers to pick and choose among prosecution targets. Some, though by no means all, trading on the basis of informational advantage is and should be illegal. But the government should be compelled to provide clear guidance as to what constitutes illegal insider trading and what constitutes legitimate, albeit aggressive, research."
~Yale Law School Professor Jonathan Macey in the WSJ