A third party to a contract can take advantage of it to act in liability against one of the contracting parties.

The fault committed by a party to a contract in the execution of said contract is likely to engage its tort liability with regard to third parties to the contract.

In other words, a third party X to a contract between Y and Z can engage the tort liability of Y on the basis of the breach by Y of its contractual obligations towards Z if this breach caused damage to X.

This principle is old (Cass. ass. plén. 6 October 2006 n° 05-13.255), and results from the principle according to which a third party can invoke for his benefit the situation created by a contract as a legal fact, without disregarding the relative effect of contracts (…)