I found money in a yeshiva. It was a single bill, which I understand does not have a siman. Is it “better” to announce it? I am discussing a case in which I will believe the boy who comes forward and says “it was a fifty shekel bill.” That is what I would want done for me, but in the other hand, there is no טביעות עין on the bill and this could be a guess— perhaps even if I would believe him, this would not be better to do? On what basis am I giving it to him? Please provide sources.
If the person in the yeshiva is going to say it is his with תביעות עין, then there is strong ground to give it back to him. However I understand that you are asking when there isn’t תביעות עין; then there is no need to return it, even if it was found in a yeshiva. If there is a possibility of תביעות עין, then in a yeshiva it should be announced. Nevertheless even you don’t have to return it , it is still a commendable thing to do “lifnim mshiras hadin”. The Shulchan Aruch Horav (Hilchos Metzia 18) explains that it is commendable to return it (If the person shows that it is very probable that it is indeed his). This is because when a person is miyayish, it isn’t like they are making it ownerless and hekfer, since it was forced upon the person, therefore it is commendable and lifnim mishuras hadin to return it. Although the money really belongs to the finder, and technically you should give maaser from this money, if he return it lifnim mishuras hadin he doesn’t have to give maaser from it (see Mishpat Hoaveida 159 Sharei Tzedek 125 in the name of R’ Eliyashiv zt”l that since it is being returned because of the din of lifnim mshuras hadin, it isn’t considered as if he was konah it and now he is giving it away.)
CH:M 262-21, SM”A ibid 41. It is controversial if people in a yeshiva are automatically considered a talmid chachom regarding returning thier lost item with תביעות עין, R’ N. Karlitz shlit”a (brought in Hashovas Aveida Kehalacha 4 ftnt. 24) says they are considered talmidei chachomim for this and R’ M. Feinstein Zt”l (Teshuva 16 at the end of Hashovas Aveida Khalacha) said that it isn’t automatic that anyone learning in a yeshiva is considered a talmid chochom for this. Hashovas Aveida Khialacha 5-5 ftnt. 21.