But that understates the case. Insider trading is actually an active good. Markets work best when goods are priced accurately, which in the context of stocks means that firms' stock prices should accurately reflect their strengths and weaknesses. If a firm is involved in a giant Enron-style scam, the price should be correspondingly lower. But, of course, until the Enron fiasco was unearthed, its stock price decidedly did not reflect that it was cooking the books. That wouldn't have happened if insider trading had been legal. The many Enron insiders who knew what was going on would have sold their shares, the price would have corrected itself and disaster might have been averted.