Daf Yomi - Beitza 28 - Taking Something Without Permission

The Gemora relates an incident that there were seven fish delivered to the house of Rebbe and five of them were found in Rebbe Chiya's house. The Gemora states that Rebbe's son, Rabbi Shimon was not particular that Rebbe Chiya received a larger portion than he did. It is evident from the Gemora that Rebbe Chiya took the fish by himself and Rabbi Shimon did not give them to him.

Sefer Tal Torah brings a proof from this Gemora that one is permitted to take something from someone else without his permission if it is known that he will not be particular about it. This is the opinion of the Shach (C"M 358) and not like the Hagaos Ashri and Tosfos in Bava Metzia (22a).

Tal Torah concludes that perhaps it is not a proof since we could speculate that Rabbi Shimon gave Rebbe Chiya a larger portion many times in the past and therefore everyone would agree that Rebbe Chiya would be permitted to take extra without permission.

I noticed that Kollel Iyun Hadaf here offers another distinction between this incident and the case that Tosfos is referring to. Rashi's words imply that Rebbe merely left the fish in a place where he normally left things for any of the Talmidim to take; he did not specifically designate the fish for Rebbe Chiya. Accordingly, Rebbe Chiya, who was one of the Talmidim, had permission to take it even though Rebbe did not give it specifically to him.