When reports surfaced in the spring of 2001 that publicly traded software company AremisSoft had inflated its earnings to boost its stock price, the case looked like a straightforward, open-and-shut securities fraud involving the company and some of its principles. The next year, the U.S. Securities Exchange Commission brought charges against the company that resulted in a $500 million settlement. By then, the Nasdaq had delisted AremisSoft and a federal grand jury had indicted the co-chief executive officers, Roys Poyiadjis and Lycourgos Kyprianou, for securities fraud. But the widening case resurfaced Monday when U.S. prosecutors in the Southern District of...