By Catherine Fredenburgh (May 11, 2006, 12:00 AM EDT) -- Until the Supreme Court's decision in Central Bank of Denver v. First Interstate Bank of Denver, 511 U.S. 164 (1994), plaintiffs in private actions routinely alleged that secondary actors who did not directly engage in conduct proscribed by the securities laws were nevertheless liable if they knowingly rendered substantial assistance to a defendant who had engaged in securities violations. This avenue became unavailable when, in Central Bank, the Supreme Court held that the securities laws "prohibit only the making of a material misstatement (or omission) or the commission of a manipulative act" and the "proscription does not include giving aid to a person who commits a manipulative or deceptive act." 511 U.S. at 177. Ever since Central Bank, courts have wrestled with the issue of what constitutes "the making of a material misstatement or omission or the commission of a manipulative or deceptive act" for purposes of holding secondary actors liable under the securities laws. While the law concerning liability for material misrepresentations and omission pursuant to Rule 10-5(b) is clear, the law governing liability for manipulative or deceptive acts pursuant to Rule 10b-5(a) and (c) is unsettled....