918. One Who Did Not Join an Eiruv

Eiruvin 2:1

If all the residents of a courtyard make an eiruv except for one, that person makes carrying prohibited for them all. This is so whether he chose not to join the eiruv or merely forgot to do so. The result is that none of the residents may carry from their homes to the courtyard or vice versa. If the person who did not join the eiruv forgoes his share of the courtyard in favor of the other residents, they are then permitted to carry from their homes to the courtyard and vice versa, though not to this person’s home. If he forgoes rights to both his house and to his share of the courtyard, then they may all carry - the others because he gave up his rights to his house and the courtyard in their favor, and this individual because he no longer owns a domain. Rather, he is considered like a guest, whose presence does not affect the right to carry to and from the courtyard.

Eiruvin 2:2

If a person forgoes rights to his property without specifying his intentions, it is presumed that he has only forgone his share in the courtyard but not rights to his house. He must make an explicit declaration to every resident of the courtyard that “I forgo my domain to you, and to you and to you.” An inheritor may forgo ownership of a domain; even if the one leaving him the property died on that Shabbos, the inheritor may act in place of the original owner in all ways. It is permissible to forgo one’s ownership rights even on Shabbos itself.