Formal validity of the agreement on a choice of applicable law
Article 23
1. The agreement referred to in Article 22 shall be expressed in writing, dated and signed by both spouses. Any communication by electronic means which provides a durable record of the agreement shall be deemed equivalent to writing. 2. If the law of the Member State in which both spouses have their habitual residence at the time the agreement is concluded lays down additional formal requirements for matrimonial property agreements, those requirements shall apply. 3. If the spouses are habitually resident in different Member States at the time the agreement is concluded and the laws of those States provide for different formal requirements for matrimonial property agreements, the agreement shall be formally valid if it satisfies the requirements of either of those laws. 4. If only one of the spouses is habitually resident in a Member State at the time the agreement is concluded and that State lays down additional formal requirements for matrimonial property agreements, those requirements shall apply.