Article 485 of Civil Code

1 - If a third party establishes title to part of the thing sold or a right of a third party over it is established, and the purchaser's resulting loss reaches an extent that, had he known of it, he would not have concluded the contract, he may return the thing sold and the benefits he derived from it and be compensated within the limits prescribed by the preceding Article. - If the purchaser chooses to retain the thing sold, or the loss he sustained does not reach the extent specified in the first paragraph, he may only claim compensation for the damage he sustained by reason of the third party's entitlement, in accordance with the provisions of the preceding Article.