1. If a person owned a barrel of wine in partnership with all of the residents of his Mavoy, an Eruv is unnecessary.
2. There is a dispute about a case of partners, where one owns the wine and one owns the oil.
3. There is a dispute about a Tevul Yom who touches oil that is floating on wine (and both liquids are Terumah).
4. Rebbi Eliezer ben Tadai argues with opinions in our Mishnah.
5. Rav Yosef explains the opinion of Rebbi Eliezer ben Tadai differently.
A BIT MORE
1. Since they jointly own a barrel of wine, they already have accomplished the purpose of the Eruv and Shituf.
2. Tana Kama: It is not an automatic Eruv (and Shituf). Rebbi Shimon: It is an automatic Eruv.
3. Rabanan: The Tevul Yom does not render the wine underneath the oil Tamei. Rebbi Yochanan ben Nuri: All of the liquids are considered connected.
4. He says that even if the people in the Mavoy jointly bought a barrel of wine, it is not deemed an automatic Eruv.
5. Rav Yosef explains that even Rebbi Eliezer ben Tadai maintains that jointly owned wine suffices to act as a Shituf for the Mavoy, but it does not automatically make an Eruv for the Chatzer (which is necessary in order to permit carrying in the Chatzer). The other Tana'im maintain that if the Shituf is valid, then there is automatically a good Eruv.