2,352. Basar Shenisaleim Min Ha'ayin

Maachalos Assuros 8:12

Similar to the situation in the previous halacha, if meat is found in the possession of a non-Jew and we don’t know where he bought it, if most meat sellers are Jewish, it is permitted. This is the case under Biblical law; the Sages prohibited any meat found in the market or in the possession of a non-Jew even when all the butchers and sellers are Jewish. Not only that, even if one bought meat and left it in his house but it was out of his sight, it is prohibited unless it has an identifying mark that he would definitely recognize, or unless it was wrapped and sealed.

Maachalos Assuros 8:13

Let’s say that someone suspended a utensil that was full of pieces of meat, the utensil broke and all the meat fell to the ground. If there are no identifying marks and he can’t recognize the meat, it’s prohibited. This is because of the possibility that the meat in the utensil might have been dragged away by an animal and this is some other meat.