Q: I found a lost item and publicized it, but nobody came to claim it. What should I do with the item now?

A: This depends on the item. Something that is irreplaceable, either because of its uniqueness or its sentimental value to the owner, you are required to hold. You are considered a shomer (guardian) on the item until the owner is identified.

Current Poskim, though, allow you to use most items which are replaceable for yourself, or to sell the item for a fair value after a reasonable amount of time passes. You should keep a “hashavas aveidah” pad in which you record the lost item, any relevant simanim, and its value. (Used items should be valued in their current condition.) You may then use the item or the proceeds of the sale. If the owner should ever turn up, give him the equivalent of the item’s value (C.M. 267:21; Hashavas Aveidah K’halachah 6:1-2).

The same applies to food items that are liable to spoil (Sma 267:30). It can also be done for items that have no siman, but were picked up before the owner was aware (yei’ush shelo midaas), where the halacha is “yehei munach ad sheyavo Eliyahu” (let it sit until Eliyahu arrives) (Igros Moshe, C.M. 2:45d).