26 CFR § 1.475(c)-2 - Definitions - security.
(3) A REMIC residual interest, or an interest or arrangement that is determined by the Commissioner to have substantially the same economic effect, if the residual interest or the interest or arrangement is acquired on or after January 4, 1995.
(b) Synthetic debt that § 1.1275-6(b) treats the taxpayer as holding. If § 1.1275-6 treats a taxpayer as the holder of a synthetic debt instrument (within the meaning of § 1.1275-6(b)(4)), the synthetic debt instrument is a security held by the taxpayer within the meaning of section 475(c)(2)(C).
(c) Negative value REMIC residuals acquired before January 4, 1995. A REMIC residual interest that is described in paragraph (c)(1) of this section or an interest or arrangement that is determined by the Commissioner to have substantially the same economic effect is not a security within the meaning of section 475(c)(2).
(1) Description. A residual interest in a REMIC is described in this paragraph (c)(1) if, on the date the taxpayer acquires the residual interest, the present value of the anticipated tax liabilities associated with holding the interest exceeds the sum of -
(i) If a transferee taxpayer acquires a residual interest with a basis determined by reference to the transferor's basis, then the transferee is deemed to acquire the interest on the date the transferor acquired it (or is deemed to acquire it under this paragraph (c)(2)(i)).