15 U.S. Code § 78k - Trading by members of exchanges, brokers, and dealers
When not in contravention of such rules and regulations as the Commission may prescribe as necessary or appropriate in the public interest and for the protection of investors, to maintain fair and orderly markets, or to remove impediments to and perfect the mechanism of a national market system, the rules of a national securities exchange may permit (1) a member to be registered as an odd-lot dealer and as such to buy and sell for his own account so far as may be reasonably necessary to carry on such odd-lot transactions, and (2) a member to be registered as a specialist. Under the rules and regulations of the Commission a specialist may be permitted to act as a broker and dealer or limited to acting as a broker or dealer. It shall be unlawful for a specialist or an official of the exchange to disclose information in regard to orders placed with such specialist which is not available to all members of the exchange, to any person other than an official of the exchange, a representative of the Commission, or a specialist who may be acting for such specialist:
If because of the limited volume of transactions effected on an exchange, it is in the opinion of the Commission impracticable and not necessary or appropriate in the public interest or for the protection of investors to apply any of the foregoing provisions of this section or the rules and regulations thereunder, the Commission shall have power, upon application of the exchange and on a showing that the rules of such exchange are otherwise adequate for the protection of investors, to exempt such exchange and its members from any such provision or rules and regulations.
It shall be unlawful for a member of a national securities exchange who is both a dealer and a broker, or for any person who both as a broker and a dealer transacts a business in securities through the medium of a member or otherwise, to effect through the use of any facility of a national securities exchange or of the mails or of any means or instrumentality of interstate commerce, or otherwise in the case of a member, (1) any transaction in connection with which, directly or indirectly, he extends or maintains or arranges for the extension or maintenance of credit to or for a customer on any security (other than an exempted security) which was a part of a new issue in the distribution of which he participated as a member of a selling syndicate or group within thirty days prior to such transaction:
 So in original. Probably should be followed by a comma.
1994—Subsec. (d)(1)(ii). Pub. L. 103–325 inserted “or any small business related security” after “mortgage related security”.
1993—Subsec. (a)(1)(E). Pub. L. 103–68, § 1(1), struck out “(other than an investment company)” after “trust”.
Subsec. (a)(1)(H), (I). Pub. L. 103–68, § 1(2)–(4), added subpar. (H) and redesignated former subpar. (H) as (I).
1984—Subsec. (d)(1). Pub. L. 98–440 designated existing provisions of par. (1) as cl. (i) and added cl. (ii).
1978—Subsec. (a)(3). Pub. L. 95–283 substituted “February 1, 1978” for “May 1, 1975”, and “February 1, 1979” for “May 1, 1978” in two places.
1975—Subsec. (a). Pub. L. 94–29, § 6(2), prohibited stock exchange members from effecting any transaction on the exchange for its own account, the account of an associated person, or an account with respect to which the member or an associated person exercises investment discretion, exempted from that prohibition 8 types of transactions, and authorized the Commission, as it deems necessary or appropriate in the public interest or for the protection of investors, to regulate or prohibit the specifically exempted transactions, certain transactions otherwise that on a national securities exchange, and transactions on a national securities exchange effected by a broker or dealer not a member thereof for the account of such broker or dealer, the account of an associated person, or an account with respect to which such broker, dealer, or associated person exercises investment discretion.
Subsec. (b). Pub. L. 94–29, § 6(2), struck out requirement that specialist’s dealings be limited to those transactions reasonably necessary to permit him to maintain a fair and orderly market, expanded the Commission’s rulemaking authority in the area of specialist’s dealings so that the Commission may define responsibilities and restrict activities of specialists in response to changing conditions in the market, expanded the standards to be followed by the Commission in exercising its rulemaking power to include the maintenance of fair and orderly markets and the removal of impediments to and the perfection of the mechanism of a national market system, and inserted specific reference to the Commission’s power to limit the activity of a specialist to that of a broker or dealer.
Subsec. (e). Pub. L. 94–29, § 6(3), struck out subsec. (e) which directed the Commission to make a study, to be submitted on or before Jan. 3, 1936, of the feasibility of segregating the functions of dealer and broker.
1954—Subsec. (d). Act Aug. 10, 1954, reduced from 6 months to 30 days the prohibition period against extending credit to purchasers of a new issue by dealers.
Amendment by act Aug. 10, 1954, effective 60 days after Aug. 10, 1954, see note under section 77b of this title.