26 USC 1236 - Dealers in securities

(a) Capital gains 
Gain by a dealer in securities from the sale or exchange of any security shall in no event be considered as gain from the sale or exchange of a capital asset unless
(1) the security was, before the close of the day on which it was acquired (or such earlier time as the Secretary may prescribe by regulations), clearly identified in the dealers records as a security held for investment; and
(2) the security was not, at any time after the close of such day (or such earlier time), held by such dealer primarily for sale to customers in the ordinary course of his trade or business.
(b) Ordinary losses 
Loss by a dealer in securities from the sale or exchange of any security shall, except as otherwise provided in section 582 (c), (relating to bond, etc., losses of banks), in no event be considered as ordinary loss if at any time after November 19, 1951, the security was clearly identified in the dealers records as a security held for investment.
(c) Definition of security 
For purposes of this section, the term security means any share of stock in any corporation, certificate of stock or interest in any corporation, note, bond, debenture, or evidence of indebtedness, or any evidence of an interest in or right to subscribe to or purchase any of the foregoing.
(d) Special rule for floor specialists 

(1) In general 
In the case of a floor specialist (but only with respect to acquisitions, in connection with his duties on an exchange, of stock in which the specialist is registered with the exchange), subsection (a) shall be applied
(A) by inserting the 7th business day following before the day the first place it appears in paragraph (1) and by inserting 7th business before day in paragraph (2), and
(B) by striking the parenthetical phrase in paragraph (1).
(2) Floor specialist 
The term floor specialist means a person who is
(A) a member of a national securities exchange,
(B) is registered as a specialist with the exchange, and
(C) meets the requirements for specialists established by the Securities and Exchange Commission.
(e) Special rule for options 
For purposes of subsection (a), any security acquired by a dealer pursuant to an option held by such dealer may be treated as held for investment only if the dealer, before the close of the day on which the option was acquired, clearly identified the option on his records as held for investment. For purposes of the preceding sentence, the term option includes the right to subscribe to or purchase any security.