(a) Identification of the basis for exemption. An identification of a security as exempt from mark to market does not satisfy section 475(b)(2) if it fails to state whether the security is described in—

(1) Either of the first two subparagraphs of section 475(b)(1) (identifying a security as held for investment or not held for sale); or

(2) The third subparagraph thereof (identifying a security as a hedge).

(b) Time for identifying a security with a substituted basis. For purposes of determining the timeliness of an identification under section 475(b)(2), the date that a dealer acquires a security is not affected by whether the dealer's basis in the security is determined, in whole or in part, either by reference to the basis of the security in the hands of the person from whom the security was acquired or by reference to other property held at any time by the dealer. See § 1.475(a)-3 for rules governing how the dealer accounts for such a security if this identification is not made.

(c) Integrated transactions under § 1.1275-6—(1) Definitions. The following terms are used in this paragraph (c) with the meanings that are given to them by § 1.1275-6: integrated transaction, legging into, legging out, qualifying debt instrument, § 1.1275-6 hedge, and synthetic debt instrument.

(2) Synthetic debt held by a taxpayer as a result of legging in. If a taxpayer is treated as the holder of a synthetic debt instrument as the result of legging into an integrated transaction, then, for purposes of the timeliness of an identification under section 475(b)(2), the synthetic debt instrument is treated as having the same acquisition date as the qualifying debt instrument. A pre-leg-in identification of the qualifying debt instrument under section 475(b)(2) applies to the integrated transaction as well.

(3) Securities held after legging out. If a taxpayer legs out of an integrated transaction, then, for purposes of the timeliness of an identification under section 475(b)(2), the qualifying debt instrument, or the § 1.1275-6 hedge, that remains in the taxpayer's hands is generally treated as having been acquired, originated, or entered into, as the case may be, immediately after the leg-out. If any loss or deduction determined under § 1.1275-6(d)(2)(ii)(B) is disallowed by § 1.1275-6(d)(2)(ii)(D) (which disallows deductions when a taxpayer legs out of an integrated transaction within 30 days of legging in), then, for purposes of this section and section 475(b)(2), the qualifying debt instrument that remains in the taxpayer's hands is treated as having been acquired on the same date that the synthetic debt instrument was treated as having been acquired.