The provisions of section
77e of this title shall not apply to—
(3)
transactions by a dealer (including an underwriter no longer acting as an underwriter in respect of the security involved in such transaction), except—
(A)
transactions taking place prior to the expiration of forty days after the first date upon which the security was bona fide offered to the public by the issuer or by or through an underwriter,
(B)
transactions in a security as to which a registration statement has been filed taking place prior to the expiration of forty days after the effective date of such registration statement or prior to the expiration of forty days after the first date upon which the security was bona fide offered to the public by the issuer or by or through an underwriter after such effective date, whichever is later (excluding in the computation of such forty days any time during which a stop order issued under section
77h of this title is in effect as to the security), or such shorter period as the Commission may specify by rules and regulations or order, and
(C)
transactions as to securities constituting the whole or a part of an unsold allotment to or subscription by such dealer as a participant in the distribution of such securities by the issuer or by or through an underwriter.
With respect to transactions referred to in clause (B), if securities of the issuer have not previously been sold pursuant to an earlier effective registration statement the applicable period, instead of forty days, shall be ninety days, or such shorter period as the Commission may specify by rules and regulations or order.