The date of filing of a European patent application shall be the date on which the requirements laid down in the Implementing Regulations are fulfilled. 

Unless this Convention provides otherwise, the European patent application as an object of property shall, in each designated Contracting State and with effect for such State, be subject to the law applicable in that State to national patent applications. 

An assignment of a European patent application shall be made in writing and shall require the signature of the parties to the contract.