P.R. Laws tit. 31, § 3820
In the sale of real estate made for a fixed price and not at the rate of a specified sum for a unit of measure or number, the increase or decrease of the same shall not be considered, even when greater or less area or amount than that stated in the contract may be found.
The same shall take place when two or more estates should be sold for a single price; but, if besides mentioning the boundaries, which are indispensable in every conveyance of real estate, their area and number should be designated in the contract, the vendor shall be obliged to deliver all that is included within said boundaries, even when they exceed the area or number specified in the contract; and, should he not be able to do it, he shall suffer a reduction in the price, in proportion to what is lacking in the area or number, unless the contract be annulled by reason of the vendee not accepting the failure to deliver what had been stipulated.
History —Civil Code, 1930, § 1360.