Under the Uniform Commercial Code, section 4-403 any signer on an account may direct that it be closed (check your state's version of that section of the UCC). Unless the bank had some sort of account contract language that altered the effect of section 4-403, a second signature would not be required on the form, even if the account to be closed is joint.
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John S. Burnett
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Fighting for Compliance since 1976
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