26 CFR § 1.1236-1 - Dealers in securities.
(a) Capital gains. Section 1236(a) provides that gain realized by a dealer in securities from the sale or exchange of a security (as defined in paragraph (c) of this section) shall not be considered as gain from the sale or exchange of a capital asset unless:
(1) The security is, before the expiration of the thirtieth day after the date of its acquisition, clearly identified in the dealer's records as a security held for investment or, if acquired before October 20, 1951, was so identified before November 20, 1951; and
(2) The security is not held by the dealer primarily for sale to customers in the ordinary course of his trade or business at any time after the identification referred to in subparagraph (1) of this paragraph has been made.
(b) Ordinary losses. Section 1236(b) provides that a loss sustained by a dealer in securities from the sale or exchange of a security shall not be considered a loss from the sale or exchange of property which is not a capital asset if at any time after November 19, 1951, the security has been clearly identified in the dealer's records as a security held for investment. Once a security has been identified after November 19, 1951, as being held by the dealer for investment, it shall retain that character for purposes of determining loss on its ultimate disposition, even though at the time of its disposition the dealer holds it primarily for sale to his customers in the ordinary course of his business. However, section 1236 has no application to the extent that section 582(c) applies to losses of banks.
(c) Definitions -
(1) Security. For the purposes of this section, the term security means any share of stock in any corporation, any certificate of stock or interest in any corporation, any note, bond, debenture, or other evidence of indebtedness, or any evidence of any interest in, or right to subscribe to or purchase, any of the foregoing.
(2) Dealer in securities. For definition of a dealer in securities, see the regulations under section 471.
(d) Identification of security in dealer's records.
(1) A security is clearly identified in the dealer's records as a security held for investment when there is an accounting separation of the security from other securities, as by making appropriate entries in the dealer's books of account to distinguish the security from inventories and to designate it as an investment and by (i) indicating with such entries, to the extent feasible, the individual serial number of, or other characteristic symbol imprinted upon, the individual security, or (ii) adopting any other method of identification satisfactory to the Commissioner.
(2) In computing the 30-day period prescribed by section 1236(a), the first day of the period is the day following the date of acquisition. Thus, in the case of a security acquired on March 18, 1957, the 30-day period expires at midnight on April 17, 1957.