Bava Metzia 7B

מאי שנא ליד דיין? אמר רבא, הכי קאמר: ואחר שמצא שטר שנפל ליד דיין, והיכי דמי ⁠– דכתב ביה הנפק, לא יוציאו עולמית.

The Talmud asks: What is different about the case where the promissory note fell into the possession of a judge, such that the creditor cannot retrieve it to collect the debt? Rava said this is what the baraita is saying: But in the case of another individual, who is neither the debtor nor the creditor, who found a promissory note that had already fallen into the possession of a judge, it may never be removed from his possession until proof is provided. And what are the circumstances? What does it mean that the promissory note had fallen into the possession of a judge? It is a case where the court wrote in the promissory note a ratification certifying that it examined and ratified the note and it can be used to collect the debt.

ולא מיבעיא לא כתב ביה הנפק, דאיכא למימר כתב ללות ולא לוה, אלא אפילו כתב ביה הנפק, דמקוים ⁠– לא יחזיר, דחיישינן לפירעון.

And the reason the baraita refers specifically to these circumstances is that it is not necessary to state that in a case where there is no ratification written in the promissory note that the creditor cannot use it to collect the debt; as it can be said that the debtor wrote the document because he intended to borrow the money, but he ultimately did not borrow it. Rather, the baraita states that even in a case where there is a ratification written in the promissory note, as it is now a ratified promissory note, the finder should not return it to the creditor, as we suspect that there was repayment, i.e., that the debtor may have repaid the debt, and he lost the promissory note.