Artikel 4

The Government of a country to which this Convention applies, may, at the request of, and on behalf of, the Government of any other country to which this Convention applies, cause any ship which belongs to the last-mentioned country to be measured and marked at the expense of the owner of the ship in accordance with the provisions of this Convention, and to issue an International Tonnage Certificate to such a ship under its own responsibility. In the same way measuring and marking may be carried out for a ship which is being built to the order of an owner in another country to which this Convention applies.
Any certificate so issued shall contain a statement to the effect that it has been issued at the request of the Government of the country to which the ship belongs, or is intended to belong, and such a certificate shall receive the same recognition as a tonnage certificate issued under article 3 of this Convention.
The Government which has issued such a tonnage certificate shall forward to the Government of the country to which the ship belongs, without delay, a certified copy of the Tonnage Certificate and of the Formulae of Measurement on which the certificate is based.
When a ship is transferred from a country to which this Convention applies, to any other country to which this Convention applies, the Government of the first-mentioned country shall, at the request of the Government of the last-mentioned country, forward to this Government, without delay, a certified copy of the Tonnage Certificate in force for the ship and of the Formulae of Measurement on which the certificate is based.