Mr. Laufer owned a semi-detached house, which he rented out. One day he mentioned to his tenant, Mr. Sorscher, that he was planning to sell his house.

“We are interested in buying your house,” Mr. Sorscher said. “It will save you the need to advertise.”

“How much are you offering?” asked Mr. Laufer.

Mr. Sorscher made a formal offer. Mr. Laufer gave his approval to the deal. The two worked out the details and signed a purchase agreement.

As the closing date approached, the owner of the adjacent half, attached to Mr. Laufer’s  house, came to visit Mr. Sorscher. After some casual conversation, he said, “I heard that you’re planning to buy Mr. Laufer’s house. Is that true?”

“Yes,” replied Mr. Sorscher. “Why do you ask?”

“I didn’t know that his house was for sale,” said the neighbor. “Was it advertised?”

“No,” replied Mr. Sorscher. “When Mr. Laufer mentioned that he planned to sell, I immediately made him an offer.”

“Ah, I understand,” said the neighbor. “There’s something that I’d like to discuss with you, if you have a few minutes.”

“Sure,” said Mr. Sorscher. “Sit down.”

The two sat down in the living room. “Thank G-d our family has grown,” said the neighbor. “I’ve been thinking of expanding our house.”

“That makes sense,” said Mr. Sorscher. “How do you plan to do that?”

“The simplest way is by buying the attached house and joining the two,” said the neighbor. “If Mr. Laufer’s house is up for sale, I’d like to buy it. Have you heard of the concept ‘dina d’bar metzra’?”

“No, I haven’t,” replied Mr. Sorscher. “What is that?”

“When a property is available for sale, Chazal instituted that the adjacent owner has first rights to buy it,” explained the neighbor. “This is fair and just, as he can utilize the property most efficiently to expand, so he is the one to whom it is most valuable.”

“I see where you’re heading,” said Mr. Sorscher, “but it’s too late now. We already signed a purchase agreement and are about to close on the deal.”

“Even so, the Sages required the buyer to retract his offer in favor of the adjacent owner,” replied the neighbor. “Even after the sale, the neighbor has the right to demand that the buyer sell the property to him” (C.M. 175:6).

“But I’m already living in the house,” said Mr. Sorscher. “Shouldn’t that count? My rights should not be less valid than a neighbor’s!”

“I don’t think that makes a difference,” replied the neighbor, “but let’s ask Rabbi Dayan.”

“The rights of dina d’bar metzra of a renter is subject to a dispute between the Rambam and the Rosh,” replied Rabbi Dayan. “The Rambam maintains that a renter does not have these rights, whereas the Rosh maintains that he does, since a rental is like a purchase for that time.”

“Whose opinion do we follow?” asked Mr. Sorscher.

“The Shulchan Aruch leans towards the opinion of the Rambam, whereas the Rema cites the opinion of the Rosh,” replied Rabbi Dayan. “The Acharonim leave this issue unresolved, so the final ruling depends on who has the more certain claim or is in possession (muchzak). Thus, an adjacent renter has some rights relative to an outsider, and a current tenant even more, but still less than an adjacent owner. Nonetheless, if the renter already bought the house, an adjacent owner cannot claim dina d’bar metzra rights any more, since the renter is now in possession. It would seem that signing a purchase agreement should not suffice for a current tenant. Thus, Mr. Sorscher may not follow through on the deal” (C.M. 175:59-63; Pischei Teshuvah 175:27‑28).