In general, a liquid account, denominated in monetary units (dollars, pounds, euros, etc) from which the owner has the right to make a withdrawal at any time is treated legally much the same as cash. This includes a bank account and a brokerage 'cash" account. It will not include a mutual fund account denominated in shares of stock, nor a debt which is not collectable at will. When the proceeds of a transaction are depositd into such an account, I believe that the profit (if any)m has been "realized" and that a taxable event has occurred.
Under 26 U.S.C. § 1001 a gain or loss is realized on the sale or other disposition, or exchange of property. Nothing is ssid about 'cash" or accounts with a signature authority.
Under 26 CFR 1.1001-1:
... the gain or loss realized from the conversion of property into cash, or from the exchange of property for other property differing materially either in kind or in extent, is treated as income or as loss sustained.
in Cottage Savings Ass'n v. Comm. of Internal Revenue, 499 U.S. 554, 559 (1991) The US Supreme Court wrote:
Rather than assessing tax liability on the basis of annual fluctuations in the value of a taxpayer's property, the Internal Revenue Code defers the tax consequences of a gain or loss in property value until the taxpayer "realizes" the gain or loss. The realization requirement is implicit in § 1001(a) of the Code, 26 U. S. C. § 1001(a), which defines "[t]he gain [or loss] from the sale or other disposition of property" as the difference between "the amount realized" from the sale or disposition of the property and its "adjusted basis." As this Court has recognized, the concept of realization is "founded on administrative convenience." Helvering v. Horst, 311 U. S. 112, 116 (1940).
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Section 1001(a)'s language provides a straightforward test for realization: to realize a gain or loss in the value of property, the taxpayer must engage in a "sale or other disposition of [the] property." The parties agree that the exchange of participation interests in this case cannot be characterized as a "sale" under § 1001(a); the issue before us is whether the transaction constitutes a "disposition of property."
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Neither the language nor the history of the Code indicates whether and to what extent property exchanged must differ to count as a "disposition of property" under § 1001(a). Nonetheless, we readily agree with the Commissioner that an exchange of property gives rise to a realization event under § 1001(a) only if the properties exchanged are "materially different."...
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We start with the classic treatment of realization in Eisner v. Macomber, supra. In Macomber, a taxpayer who owned 2,200 shares of stock in a company received another 1,100 shares from the company as part of a *pro rata- stock dividend meant to reflect the company's growth in value. At issue was whether the stock dividend constituted taxable income. We held that it did not, because no gain was realized.
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In Phellis and Marr, we held that the transactions were realization events. We reasoned that because a company incorporated in one State has "different rights and powers" from one incorporated in a different State, the taxpayers inPhellis and Marr acquired through the transactions property that was "materially different" from what they previously had. United States v. Phellis, 257 U. S., at 169-173;
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Taken together, Phellis, Marr, and Weiss stand for the principle that properties are "different" in the sense that is "material" to the Internal Revenue Code so long as their respective possessors enjoy legal entitlements that are different in kind or extent. Thus, separate groups of stock are not materially different if they confer "the same proportional interest of the same character in the same corporation." Marr v. United States, 268 U. S., at 540. However, they are materially different if they are issued by different corporations, id., at 541; United States v. Phellis, supra, at 173, or if they confer "differen[t] rights and powers" in the same corporation, Marr v. United States, supra, at 541. No more demanding a standard than this is necessary in order to satisfy the administrative purposes underlying the realization requirement in § 1001(a). See Helvering v. Horst, 311 U. S., at 116. For, as long as the property entitlements are not identical, their exchange will allow both the Commissioner and the transacting taxpayer easily to fix the appreciated or depreciated values of the property relative to their tax bases
Thus any exchange of property for other property which is in some significant sense different, such as interests in different mortgages of similar market value, or any sale of property causes a gain or loss to be realized.It does not matter in what sort of account the proceeds are held, or even whether the proceeds are in cash as opposed to some other sort of property. The beneficial owner realizes a gain or loss, even if s/he is not the legal owner.
