Pursuant to a legislative requirement, GAO reviewed the Securities and Exchange Commission's (SEC) new rule on unlisted trading privileges. GAO noted that: (1) under the rule, a national securities exchange extending unlisted trading privileges to an initial public offering (IPO) listed on another exchange will no longer be required to wait until the day after trading has commenced on the listing exchange to allow trading in that security; (2) the rule would allow a national securities exchange to begin trading an IPO issue immediately after the first trade in the security is reported to the Consolidated Tape; and (3) SEC complied with applicable requirements in promulgating the rule.