(a) the signature is that of the person signing; and

(b) the signer is the holder, or the signer has purported authority to sign in the name of the holder; provided that if the holder purports to act as a fiduciary either as “fiduciary” as defined in this Code or his name is signed by a person purporting to act on the holder's behalf as a fiduciary, the bank warrants that such holder or such person so signing as such fiduciary is in fact the fiduciary he purports to be and warrants that the bank has no actual knowledge that such fiduciary is committing a breach of his obligation as such fiduciary in signing such document and that it has no knowledge of such facts that its action in guaranteeing the signature amounts to bad faith; and

(c) the signer has legal capacity to sign.