QUESTIONS: The Rabanan in the Mishnah (49b) state that a person is entitled to a refund of his money if he was overcharged a sixth ("Shesus") more than the value of the merchandise, provided that he claims the Ona'ah within the amount of time it takes to have a merchant or relative assess the merchandise that he bought. The Gemara here asks what the law is in the case of Ona'ah of less than a sixth. Do the Rabanan allow the buyer to claim a refund, within the given amount of time, also when the overcharge is less than a sixth, or do they maintain that when someone is overcharged less than a sixth he automatically forfeits the extra money he paid?

There seem to be two sources from which the Gemara easily could answer this question, but the Gemara makes no mention of them at all:

(a) The Mishnah (49b) states that a person is allowed to make a claim of Ona'ah when he was charged one-sixth more than the value of the item, as long as he makes the claim within the amount of time it takes to have a merchant or relative assess the value of the item. If this entitlement applies even when a person is overcharged less than a sixth, why does the Mishnah not say so?

(b) The Beraisa later (50b) states that when a buyer is overcharged less than a sixth, the sale is valid. This implies that the sale is valid and binding immediately and the buyer has no recourse. Why does the Gemara not answer its question from this statement in the Beraisa?

Moreover, the Beraisa continues and says that if the buyer is overcharged more than a sixth, the sale is invalid. If he is overcharged exactly a sixth, the sale is valid and the Ona'ah must be returned. The Beraisa concludes, "Both this and this [may claim Ona'ah] within the amount of time it takes to show the merchandise to a merchant or relative." "Both this and this" refers to Ona'ah of a sixth and Ona'ah of more than a sixth. This implies that when the buyer is overcharged less than a sixth he has no recourse; he immediately forfeits the extra money that he paid. Why does the Gemara not answer its question from the Beraisa?

(a) The SHITAH MEKUBETZES answers that since there is no other source in the Mishnayos for what happens when a person is overcharged by less than a sixth, one may assume that the Mishnah here intends to include this Halachah in its words. Accordingly, it is unclear from the Mishnah alone whether Ona'ah of less than a sixth has the same law as Ona'ah of a sixth.

(b) The RASHASH offers two answers for why the Gemara does not answer its question from the Beraisa.

1. The Gemara later (51a) quotes Rabah who explains that Rebbi Nasan's opinion in the Beraisa is that in a case of Ona'ah of a sixth, the buyer has the option to receive the extra money back, or to cancel the sale in its entirety. Accordingly, there is no clear proof from the Beraisa that one may not get his money back in the case of Ona'ah of less than a sixth.

2. Alternatively, the Rashash suggests that the Gemara indeed answers its question from the Beraisa. When the Gemara quotes Rava's statement and then supports it with this Beraisa, it is proving from the Beraisa that one cannot claim money he was overcharged when the amount was less than a sixth. (Y. Montrose)

QUESTION: The Gemara presents the basic guidelines for Ona'ah. If a buyer is overcharged less than a sixth, the sale is valid. If he is overcharged more than a sixth, the sale is invalid. If he is overcharged exactly one sixth, the sale is valid and the Ona'ah must be returned. The Mishnah later (51a) teaches that the prohibition of Ona'ah also applies to a buyer, such as when he knowingly lets the seller sell him an item below its value and does not alert the seller that he is not charging the correct price. The guidelines of Ona'ah for a buyer are parallel to that of a seller (that is, if a seller is underpaid less than a sixth, the sale is valid, and so on).

Nowadays, many countries (including Israel) have a law which states that a store which lists prices on the items which it lays out for sale must honor those prices, even if the correct price (which is displayed on the computer screen after the item's barcode has been scanned) is higher. The author of SEFER SHIMRU MISHPAT (#37) writes that a man asked him about an incident which happened to him at an Israeli supermarket. He saw an item which was clearly marked incorrectly, with a price of 2.30 shekels. He brought a number of the items to the checkout counter to buy, and the scan of the barcode showed that the price was 12.30 and not 2.30. He insisted that the price marked on the tag be honored, and he cited the law that entitled him to that price. The store manager was called over to settle the dispute between the buyer and the cashier. The manager called the buyer unreasonable and insensitive, but said that if he insists he may buy the items at the lower price. Afterwards, the man asked a Rav whether the Halachah permits him to keep the items or whether he must pay back the difference.

ANSWER: The SHIMRU MISHPAT explains that most Poskim rule that in this type of case, the prevailing custom of merchants (or the law of the land) overrides the prohibition of Ona'ah. Accordingly, when an item was on sale and is still marked as such, the buyer is entitled to pay the price which is marked and not the price that appears when the barcode is scanned.

However, this ruling does not apply in this particular case. The logic behind this law is for the buyer's protection: a buyer should not be enticed to buy an item which is marked with a lower price when in fact he will be charged a higher price for it when the barcode is scanned. When a buyer sees that the price of an item clearly is in error, and it is clear to him that the item never sold for such a price, he may not insist on paying this price. This is certainly the case when the buyer can see the error, such as a digit that was accidentally left out of the price (the price was marked as 2.30 instead of 12.30). The Shimru Mishpat says that in this case there is no prevailing custom that requires that the store must honor the price as marked. The manager did not forgo the difference due to custom or law, but rather he did so out of pressure and to avoid further confrontation (see REMA CM 333:8). For this and other reasons, the Shimru Mishpat rules that the buyer must reimburse the store for the difference in price. (Y. Montrose)