| Contracting Parties | Signature | Ratification (Instrument deposited on) |
Entry into force |
| AUSTRIA | 10.09.1964 | 31.08.1965 | 30.09.1965 |
| BELGIUM | 10.09.1964 | 06.02.1975 | 08.03.1975 |
| GREECE | 10.09.1964 | 01.07.1977 | 31.07.1977 |
| ITALY | 10.09.1964 | 07.07.1972 | 06.08.1972 |
| LUXEMBOURG | 10.09.1964 | 20.05.1965 | 30.09.1965 |
| NETHERLANDS | 10.09.1964 | 18.05.1967 | 17.06.1967 |
| TURKEY** | 10.09.1964 | 20.03.1970 | 19.04.1970 |
| + PORTUGAL | 10.09.1964 | 15.10.1980 | 14.11.1980 |
| + accession
** denunciation |