Yerushalmi Bava Batra 10:5 ירושלמי בבא בתרא י׳:ה׳

MISHNAH: If somebody paid off part of his debt, deposited his bond with a third party,⁷⁸The text of the bond cannot be changed; that would be falsifying it. The partial payment cannot be noted on the bond since everything written after the signature of the witnesses must be disregarded. It would be possible to write a separate receipt, cf. Mishnah 10. The alternative is to hand the bond to a third party as trustee with the instruction to deliver the document to the debtor upon payment of the remainder of the debt. and told him, if I have not paid him by date x, return the bond to him. If the time has passed while he did not pay, Rebbi Yose says, he shall return it; Rebbi Jehudah says, he shall not return it⁷⁹R. Yose considers the condition as valid; R Jehudah treats it as asmakhta (Note 70)..
If somebody’s bond became illegible, he presents witnesses about it to the court and they confirm for him: The bond of Mr. X, son of Mr. Y, dated from day Z became illegible; U and V were his witnesses.

HALAKHAH: “One writes a document of indebtedness,” etc. It was stated, forfaits⁷⁰Whether a private contract containing forfaits automatically is enforceable in court or is to be considered an asmakhta contract (cf. Giṭṭin 5:9, Note 213) is a subject of controversy already of Tannaïm; Tosephta Bava meṣia‘ 1:16.. Rebbi Abbahu collected, Rebbi Aḥa collected, Rebbi Immi collected⁷¹In the third generation of Amoraïm, forfaits were considered enforceable, following Egyptian and Greek practices. By the fifth generation, practice had changed and forfaits were considered asmakhta, following Roman law; cf. Sefer Ha‘iṭṭur vol. 1, 49b, Note 42; Taubenschlag (Note 13) pp. 205 ff... Rebbi Jonah and Rebbi Yose did not collect. ⁷²Cf. Giṭṭin 5:9, Notes 213–214. Rebbi Mana said, even though Rebbi Yose did not collect forfaits, he agrees if one gave his son to artisans and they mutually agreed to forfaits, he collects.

“One writes a sale contract for the seller,” etc. Rebbi Uqba said, it was stated in Ketubot⁷⁶The baraita collection of the school of Levi about Ketubot. of the school of Levi: If one said, my document was lost, the court writes him a confirmation⁷⁷This is really a commentary on Mishnah 9. Not only if part of a document became illegible can the holder go to court, present witnesses to the court who testify as to the exact wording that was lost, and get a court declaration certifying the text as belonging to the document, but even a lost document can be replaced by a court-issued confirmation if verified by witnesses and agreed to by the other party. The statement is inserted here as preliminary to the next statement about documents of arbitration mentioned in Mishnah 7.. It was stated: Rabban Simeon ben Gamliel said, even for documents of arbitration one writes him a confirmation.