How many people must be present for a valid declaration that property is now ownerless: Nedarim 43a, 45a
Declaring property claimable for some people and not others: Bava Metzia 30b
Declaring the property to be ownerless, using a form of speech which is unclear, known as a "Yad": Nedarim 7a
Whether a declaration which removes ownership of an item is equivalent to a declaration of donation to tzedakah: Nedarim 7a
Legal status of ownerless property
Whether property leaves the ownership of the owner before it is claimed by another, or not: Nedarim 43a-b
Considering an item to be under a person's ownership if he is guarding the area in which it lies: Pesachim 6b
Payment for damage done to or by ownerless property, if someone claims the ownerless property item later: Bava Kama 13b
Payment for damage which was done by an animal which was then declared ownerless: Bava Kama 13b
Whether ownerless property is free from the requirement of Peah: Pesachim 56b
The requirement of tithing a field which one declares ownerless, and then harvests: Nedarim 44b; Temurah 6a
The requirement of leaving the corner of the field for paupers, if one declares his field ownerless and then harvests it: Nedarim 44b; Temurah 6a
The requirement of leaving forgotten grapes, and individual [non-bunch] grapes on a vine which one declares ownerless and then harvests: Nedarim 44b
The requirement of leaving forgotten grain from a field which one declares ownerless and then harvests: Nedarim 44b
What-ifs
Time-frame for revoking a declaration which revoked ownership of a field, before/after it is claimed by another: Nedarim 43b-45a
Time-frame for revoking a declaration which revoked ownership of a field, where he had declared that it would be ownerless for a specific, limited time: Nedarim 44a
The status of property which had been condemned for destruction because of a court's verdict, if the court's verdict is then nullified because of new information: Keritot 24a
The status of property which one person attempts to give to another, but the intended recipient declines to accept: Keritot 24a-b