if the law of a Contracting State so permits, and subject to Article 76, paragraph 1, with the central industrial property office or other competent authority of that State. Any application filed in this way shall have the same effect as if it had been filed on the same date with the European Patent Office.
Paragraph 1 shall not preclude the application of legislative or regulatory provisions which, in any Contracting State:
govern inventions which, owing to the nature of their subject-matter, may not be communicated abroad without the prior authorisation of the competent authorities of that State, or
prescribe that any application is to be filed initially with a national authority, or make direct filing with another authority subject to prior authorisation.
See the notice from the EPO of 30.01.2018 concerning changes to the filing options available in Belgium for European patent applications and international applications (OJ EPO 2018, A17) and the notice from the EPO of 20.11.2019 concerning changes to the filing options available in San Marino for European patent applications and international applications (OJ EPO 2019, A96).