In addition to the prospectus permitted or required in subsection (a) of this section, the Commission shall by rules or regulations deemed necessary or appropriate in the public interest or for the protection of investors permit the use of a prospectus for the purposes of subsection (b)(1) ofsection
of this title which omits in part or summarizes information in the prospectus specified in subsection (a) of this section. A prospectus permitted under this subsection shall, except to the extent the Commission by rules or regulations deemed necessary or appropriate in the public interest or for the protection of investors otherwise provides, be filed as part of the registration statement but shall not be deemed a part of such registration statement for the purposes of section
of this title. The Commission may at any time issue an order preventing or suspending the use of a prospectus permitted under this subsection, if it has reason to believe that such prospectus has not been filed (if required to be filed as part of the registration statement) or includes any untrue statement of a material fact or omits to state any material fact required to be stated therein or necessary to make the statements therein, in the light of the circumstances under which such prospectus is or is to be used, not misleading. Upon issuance of an order under this subsection, the Commission shall give notice of the issuance of such order and opportunity for hearing by personal service or the sending of confirmed telegraphic notice. The Commission shall vacate or modify the order at any time for good cause or if such prospectus has been filed or amended in accordance with such order.