Yehuda ran a small sefarim store in his yeshiva; he sold sefarim during the lunch break.
One Thursday afternoon, Shlomo came by. “My cousin is becoming bar mitzvah this Shabbos,” he said. “Any sefarim that you can recommend?”
Yehuda suggested various sefarim, but Shlomo didn’t consider them suitable.
“A new sefer just came out about tefillin,” Yehuda said. “Take a look at it!”
Shlomo perused the sefer. “This looks very interesting!” he said. “I think my cousin will like it. How much is it?”
“It’s new, so I don’t remember the exact price,” replied Yehuda, “I have to check the price list, but it’s about $30.”
“That should be fine,” said Shlomo.
Yehuda checked the price list. “The sefer costs $28,” he said.
“Great!” said Shlomo. “I’ll take it. Please gift wrap it!”
Yehuda wrapped the sefer; Shlomo took it.
The following week, Yehuda met Shlomo. “How was the bar mitzvah?” he asked.
“It was lovely!” replied Shlomo. “My cousin read the parsha really well and gave a lomdishe drasha. He loved the sefer!”
“I’m glad to hear,” said Yehuda. “I wanted to tell you, though, that I misread the price list. $28 was the line above, but this sefer is actually $31, so you owe another $3.”
“You can’t change the price now,” objected Shlomo. “I already gave my cousin the sefer!”
“I’m not changing the price,” argued Yehuda. “$31 was the price all along. I just misread the price list.”
“Anyway, small price differentials, less than a sixth, don’t carry a monetary claim of onaah – unfair pricing,” added Shlomo. “We learned about that last year (Bava Metziah 49b).”
“This was a clear error, though,” replied Yehuda.
Yehuda and Shlomo approached Rabbi Dayan and asked:
“Does Shlomo have to pay the correct amount listed in the price list?”
“Indeed, onaah has a three-tier system: 1) A differential of less than a sixth is considered mechila. 2) A sixth must be returned, but the sale remains intact. 3) More than a sixth, the aggrieved party can nullify the sale” (C.M. 227:2-4).
“Nonetheless, these laws apply only to a misjudgment in evaluating the price. However, if there was a concrete error, like an erroneous scale measure, error in quantity, etc. – the error must be corrected, even less than a sixth, and even much later. This does not fall under the laws of onaah, but rather those of mekach taus – an erroneous sale. If not possible to correct, the sale can be voided” (C.M. and Sma 232:1).
“Similarly, if the price was agreed according to a catalogue or price list, and the seller mistakenly read the wrong price, or he mistakenly read from an outdated catalogue rather than the current one, the price should be corrected, even if there is less than a sixth differential.
“This is because here the mutual agreement of the parties was to set the price according to the price listed in the catalog. The misquoted price was not due to a misjudgment in valuation, which by its nature fluctuates, but rather to a concrete error, similar to an error in measuring” (see Hayashar V’hatov, vol. 18 [5775], pp. 71-107, Hachiluk bein Onaah l’Psika b’Taus).
“We find basis for this distinction in the following halacha. If an employer hired workers and agreed to pay them like the other workers, but he quoted them a lesser wage, he is required to pay them the amount paid to the other workers, as agreed. This is because the stated wage was erroneous in regard to the intended contractual agreement to pay like the other workers” (Rema and Nesivos 332:4; Sma 332:10).
“Even the Shach (332:15), who disagrees with this ruling, would presumably agree if the employer also erred unintentionally.
“Thus,” concluded Rabbi Dayan, “Shlomo is required to add the $3.”
Verdict: A misquoted price due to a clear error, not a misjudged evaluation, is considered an erroneous transaction, not onaah; it should be corrected even if the differential is less than a sixth.
