An allonge is a sheet of paper that is attached to a negotiable instrument, such as a bill of exchange, to provide space for additional endorsements.

The indorsement must be made either on the face of the note or on an allonge ‘so firmly affixed thereto as to become a part thereof” (UCC § 3-202[2]).” ...

If the endorsement is on an allonge, the plaintiff must show that the allonge is so firmly affixed to the note “as to become a part thereof,” as required by UCC 3-202(2).

If the lender is not the originating lender, but a subsequent transferee, courts have generally required that the transferee lender show an assignment of the note through an allonge that is ...