(Mishnah): If a person paid back part of his debt and they gave the document to a third party (rather than forcing each other to begrudging pay the sofer to write the receipts) and the borrower said to the third party, "If I do not pay (the lender) between now and day ploni, give him the document (and he will be able to collect in full)''...

If the time came and he had not paid, R. Yosi says that the third party should give the document to the lender and R. Yehuda says that he should not. (This depends on the dispute as to whether asmachta kanya - meaning, whether a conditional obligation of payment is binding (without a physical kinyan being made).

If a loan document accidently became erased, the lender should bring witnesses and come to Beis Din and (after testifying) Beis Din can validate it by saying, "Ploni ben Ploni's document became erased on day ploni and Ploni and Ploni were witnesses.''

(Gemara) - Beraisa: Itzumim (i.e. an asmachta) - R. Abahu, R. Acha and R. Ami would collect; R. Yona and R. Yosi would not collect.

R. Mana: Even though R. Yosi would not collect itzumim, he agreed that if he gave over his son to a craftsman as an apprentice and they wrote a document detailing the payment conditions; the craftsman can collect since this is his livelihood.