Option Boards Are Censured By the S.E.C.
Justice Department and Securities and Exchange Commission charge that Chicago Board Options Exchange, American Stock Exchange, Pacific Stock Exchange and Philadelphia Stock Exchange agreed for years to restrain competition by not asking to trade options already traded on other exchanges; exchanges sign consent decree with Justice Department and accept censure by SEC but do not admit any wrongdoing; existence of investigations, coupled with entry of another competitor, International Securities Exchange, has already broken down barriers that regulators complained about, and most major options are now traded on multiple exchanges; it its not year clear whether competition is benefiting investors or just brokerage firms that send orders to exchanges (M)