Distribution participant means an underwriter, prospective underwriter, broker, dealer, or other person who has agreed to participate or is participating in a distribution.
17 CFR § 242.100
Preliminary note: Any transaction or series of transactions, whether or not effected pursuant to the provisions of Regulation M ( 242.100-242.105 of this chapter), remain subject to the antifraud and antimanipulation provisions of the securities laws, including, without limitation, Section 17(a) of the Securities Act of 1933 [15 U.S.C. 77q(a)] and Sections 9, 10(b), and 15(c) of the Securities Exchange Act of 1934 [15 U.S.C. 78i, 78j(b), and 78o(c)].