Are marital agreements (pre and post marriage) enforceable? Is the position the same if the agreement is a foreign agreement?

Under the Turkish Civil Law, spouses can make marital agreements. These agreements can be made before, during and after the marriage. Under the International Private and Procedural Law and the Turkish Civil Code, for the submission to the court of a foreign agreement, apostille certification should be affixed by the component authority and certified by the notary public.