Ind. Code § 26-1-3.1-204
(a) "Endorsement" means a signature, other than that of a signer as maker, drawer, or acceptor, that alone or accompanied by other words is made on an instrument for the purpose of:
(3) incurring endorser's liability on the instrument;
but regardless of the intent of the signer, a signature and its accompanying words is an endorsement unless the accompanying words, terms of the instrument, place of the signature, or other circumstances unambiguously indicate that the signature was made for a purpose other than endorsement. For the purpose of determining whether a signature is made on an instrument, a paper affixed to the instrument is a part of the instrument.
As added by P.L.222-1993, SEC.5.