Financial instrument
(4) Financial instrument(i) Definition. For purposes of this paragraph (a), the term financial instrument includes: (A) Any interest rate, currency, equity, or commodity (as the term is used in section 864(b)(2)(B) and 1.864-2(d)) notional principal contract (as the term is used in section 475(c)(2)); or (B) Any evidence of an interest in options, forward or futures contracts, and any other similar contracts, the value of which, or any payment or other transfer with respect to which, is (directly or indirectly) determined by reference to one or more of the following: