Q. How do you handle during the Pesach Seder, the kinyan (acquisitive act) needed to have the matzos gifted to the family and guests, since matzos have to be owned by the eater?
A. Shulchan Aruch (454: 4) rules that one does not comply with the mitzva of matza, if the matza was
stolen. Mishna Berura (15) explains that the reason is a (gzeira shoveh) link to the mitzva of chalah that requires that one should separate it only from produce that belongs to him. Mishna Berura adds that if one borrowed a matza, he does comply, since when it was lent, he was expected to eat it and not to return that same piece, but rather another one or its value, and that matza actually belongs to him.
Some Poskim maintain that the host who owns the matza, should actually before he hands over to his children and guest the matza, mention that it is a present for them and then they perform a kinyan or acquisitive act when they receive it. (Sefas Emes – Suka 35a, Yad Hamelech – H. Chometz Umatza 6: 7, et. al.).
Some Poskim mention that the fact that the matza was introduced in one’s mouth and chewed before being swallowed, the physical change created by the chewing, consists on a shinui maaseh and it is in itself an acquisitive act, so the matza is swallowed is already his property. (Biur Halocho 454: 4, Imrei Binah – O.H. Pesach 24, Betzel Hachochmo 4: 172 and others).
However, many Poskim assert that since they were invited to eat, it is obvious that the portions are gifted to them, and no official declaration or act of acquisition is needed. (Imrei Binah – O.H. Pesach 24, Tzitz Eliezer 2: 37 – 13: 15 and others).
Horav Shlomo Miller’s Shlit’a opinion is similar. The Rov added that throughout the generations, all that was required was for the host to place the matza in front of the family and guests and that is all that is needed.
Rabbi A. Bartfeld as revised by Horav Shlomo Miller Shlit’a