(a) Exercise of recoupment or set-off. Except as otherwise provided in subsection (c) of this section, a bank with which a deposit account is maintained may exercise any right of recoupment or set-off against a secured party that holds a security interest in the deposit account.

(b) Recoupment or set-off not affected by security interest. Except as otherwise provided in subsection (c) of this section, the application of this Article to a security interest in a deposit account does not affect a right of recoupment or set-off of the secured party as to a deposit account maintained with the secured party.

(c) When set-off ineffective. The exercise by a bank of a set-off against a deposit account is ineffective against a secured party that holds a security interest in the deposit account which is perfected by control under RCW 62A.9A-104(a)(3), if the set-off is based on a claim against the debtor.