When a secured party's collateral is encumbered by another security interest or other lien, one of the claimants may seek to invoke the equitable doctrine of marshaling. As explained by the Supreme Court, that doctrine "rests upon the principle that a creditor having two funds to satisfy his debt, may not by his application of them to his demand, defeat another creditor, who may resort to only one of the funds." Meyer v. United States, 375 U.S. 233, 236 (1963), quoting Sowell v. Federal Reserve Bank, 268 U.S. 449, 45657 (1925). The purpose of the doctrine is "to prevent the arbitrary action of a senior lienor from destroying the rights of a junior lienor or a creditor having less security." Id. at 237. Because it is an equitable doctrine, marshaling "is applied only when it can be equitably fashioned as to all of the parties" having an interest in the property. Id. This Article leaves courts free to determine whether marshaling is appropriate in any given case. See Section 1-103.

6. Security Interests of Equal Rank. Sometimes two security interests enjoy the same priority. This situation may arise by contract, e.g., pursuant to "equal and ratable" provisions in indentures, or by operation of law. See Section 9-328(6) [Maine cite section 9-1328, subsection (6)]. This Article treats a security interest having equal priority like a senior security interest in many respects. Assume, for example, that SPX and SPY enjoy equal priority, SPW is senior to them, and SPZ is junior. If SPX disposes of the collateral under this section, then (i) SPW's and SPY's security interests survive the disposition but SPZ's does not, see Section 9-617 [Maine cite section 9-1617], and (ii) neither SPW nor SPY is entitled to receive a distribution of proceeds, but SPZ is. See Section 9-615(a)(3) [Maine cite section 9-1615, subsection (1), paragraph (c)].

When one considers the ability to obtain possession of the collateral, a secured party with equal priority is unlike a senior secured party. As the senior secured party, SPW should enjoy the right to possession as against SPX. See Section 9-609 [Maine cite section 9-1609], Comment 5. If SPW takes possession and disposes of the collateral under this section, it is entitled to apply the proceeds to satisfy its secured claim. SPY, however, should not have such a right to take possession from SPX; otherwise, once SPY took possession from SPX, SPX would have the right to get possession from SPY, which would be obligated to redeliver possession to SPX, and so on. Resolution of this problem is left to the parties and, if necessary, the courts.