CC 1405     

Art. 1405.  Sale of succession rights to coheir at risk of vendor, rescission inadmissible.

The sale of successive rights by one heir to his coheir is not subject * to rescission, if the purchaser has run no risk; as, for example, if the vendor remains bound for the payment of the debts.

* Note error in English translation of French text; "is not subject" should be "is subject."