Cal. COM § 9341

Except as otherwise provided in subdivision (c) of Section 9340, and unless the bank otherwise agrees in a signed record, a bank’s rights and duties with respect to a deposit account maintained with the bank are not terminated, suspended, or modified by any of the following: (1) The creation, attachment, or perfection of a security interest in the deposit account. (2) The bank’s knowledge of the security interest. (3) The bank’s receipt of instructions from the secured party.