If a man sells a house in a walled city, he retains the right of redemption a full year after its sale. During that time he may redeem it.

人若卖城内的住宅，卖了以后，一年之内可以赎回。在一整年，必有赎回的权柄。

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AmEx eliminated the hassle that comes with paper coupons or special codes at the point of sale by making redemption as easy as swiping your card.

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So under Treasury regulations the redemption counted as a nontaxable intragroup dividend rather than a sale.

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