Answer:
Answer by Randy Carey: Your contract with the account owner that establishes the authorized signer should indicate what powers are granted to the signer.
Answer:
Answer by John Burnett: As Randy pointed out, the authorized signer's authority is limited by the agreement that should be signed by the account owner in which the authority is given. If that agreement is silent on the question of account closing, the UCC (section 4-403) allows an authorized signer to close an account.
Adding an authorized signer to an individually-owned account does not make the account joint. It remains an individually-owned account.
First published on BankersOnline.com 3/21/11