Article 550 of the French Civil Code

The possessor is in good faith when he possesses as owner, by virtue of a title transferring ownership of which he is unaware of the defects.

He ceases to be in good faith from the moment these defects become known to him.

Original in French 🇫🇷

Article 550

Le possesseur est de bonne foi quand il possède comme propriétaire, en vertu d’un titre translatif de propriété dont il ignore les vices.

Il cesse d’être de bonne foi du moment où ces vices lui sont connus.