| Value | Description |
| ABS | American Bureau of Shipping. |
| BK | Biro Klasifikasi Indonesia. |
| BKR | Bulgarski Koraben Registar. |
| BV | Bureau Veritas. |
| CCS | China Classification Society. |
| CR | China Register. |
| CRS | Croatian Register of Shipping. |
| CSC | Choson Classification Society. |
| CSLPR | Cesky a Slovensky Lodni a Prumyslovy Registr. |
| DNV | Det Norske Veritas. |
| DSRK | Deutsche Schiffs-Revision und Klassifikation. |
| FN | Fidenavis S.A. |
| GL | Germanischer Lloyd. |
| HR | Hellenic Register of Shipping. |
| IRS | Indian Register of Shipping. |
| KR | Korean Register of Shipping. |
| LR | Lloyd’s Register. |
| NK | Nippon Kaiji Kyokai. |
| OTHER | Any other society not in the list. |
| PRS | Polish Register of Shipping. |
| RCB | Registro Cubano de Buques. |
| RDS | Regjistri Detar Shqiptar. |
| RINA | RINA Services S.p.A. |
| RINAVE | Registro Internacional Naval, SA. |
| RNR | Registrul Naval Roman. |
| RR | Rechnoj Registr R.F. |
| RRR | Russian River Register. |
| RS | Russian Maritime Register of Shipping. |
| TL | Turk Loydu Vakfi. |
| UR | Shipping Register of Ukraine. |
| VL | DNV GL. |
| VR | Vietnam Register of Shipping. |