| Name | Company Number | Date Appointed | Rating |
|---|---|---|---|
| AVINGTRANS PLC | 01968354 | 01/09/2014 | Gold |
| HERIOT RESOURCES LIMITED | SC429817 | 06/08/2012 | Silver |
| ITHACA DELTA LIMITED | 07541789 | 01/10/2013 | Dissolved |
| ITHACA NORTH SEA LIMITED | 02548026 | 01/10/2013 | Dissolved |
| ITHACA PIPELINE LIMITED | 02607087 | 31/07/2014 | Dissolved |
| Name | Company Number | Date Appointed | Date Resigned | Rating |
|---|---|---|---|---|
| Aoc/Wood Offshore Contractors Ltd | SC136875 | 19/05/2004 | 04/07/2008 | Dissolved |
| BRAE GAS MARKETING COMPANY LIMITED | 00721973 | 01/12/2000 | 13/02/2004 | Dissolved |
| COGENT SSC LIMITED | SC129351 | 01/01/2007 | 10/03/2009 | Silver |
| FUJAIRAH OIL AND GAS UK 11 LIMITED | 00638574 | 22/02/2000 | 13/02/2004 | Insolvent |
| FUJAIRAH OIL AND GAS UK 12 LIMITED | 00981126 | 01/12/2000 | 13/02/2004 | Dissolved |
| FUJAIRAH OIL AND GAS UK LLC | FC009587 | 01/06/1996 | 13/02/2004 | Dissolved |
| HARWOOD PRODUCTION SERVICES LIMITED | SC299838 | 11/04/2006 | 01/06/2007 | Dissolved |
| ITHACA ALPHA (N.I.) LIMITED | NI073431 | 01/10/2013 | 24/08/2020 | Silver |
| ITHACA CAUSEWAY LIMITED | 06167799 | 01/10/2013 | 24/08/2020 | Not Trading |
| ITHACA DORSET LIMITED | 01135213 | 31/07/2014 | 24/08/2020 | Not Trading |
| ITHACA ENERGY (UK) LIMITED | SC272009 | 01/10/2013 | 24/08/2020 | Silver |
| ITHACA ENERGY DEVELOPMENTS UK LIMITED | 07105041 | 11/12/2018 | 24/08/2020 | Bronze |
| ITHACA ENERGY HOLDINGS (UK) LIMITED | SC437615 | 01/10/2013 | 24/08/2020 | One Red Flag |
| ITHACA EPSILON LIMITED | 05979869 | 01/10/2013 | 24/08/2020 | Bronze |
| ITHACA EXPLORATION LIMITED | 05914627 | 01/10/2013 | 24/08/2020 | Gold |
| ITHACA GAMMA LIMITED | 05929104 | 01/10/2013 | 24/08/2020 | Bronze |
| ITHACA GSA LIMITED | FC033620 | 11/12/2018 | 24/08/2020 | One Red Flag |
| ITHACA MINERALS (NORTH SEA) LIMITED | SC274666 | 01/10/2013 | 24/08/2020 | Silver |
| ITHACA PETROLEUM LIMITED | 05223667 | 01/10/2013 | 24/08/2020 | Bronze |
| ITHACA SP UK LIMITED | 02586927 | 31/07/2014 | 24/08/2020 | Not Trading |
| ITHACA SPL LIMITED | 01275469 | 31/07/2014 | 24/08/2020 | Dissolved |
| JOHN WOOD GROUP PLC | SC036219 | 19/05/2004 | 30/06/2012 | Silver |
| MARATHON OIL EXPLORATION (U.K.) LIMITED | 01007674 | 01/12/2000 | 13/02/2004 | Dissolved |
| MARATHON OIL UK LIMITED | SF000275 | 01/06/1996 | 13/02/2004 | Dissolved |
| MARATHON UPSTREAM NORTH SEA (G.B.) LIMITED | 00812455 | 01/12/2000 | 13/02/2004 | Dissolved |
| MARATHON UPSTREAM U.K. LLC | FC005250 | 20/07/1998 | 13/02/2004 | Dissolved |
| NORTHERN INTEGRATED SERVICES LIMITED | SC195682 | 19/05/2004 | 17/09/2005 | Dissolved |
| OFFSHORE TRAINING FOUNDATION | SC229139 | 18/03/2002 | 01/07/2004 | Gold |
| OPITO LIMITED | SC152175 | 25/10/1999 | 31/07/2004 | Amber |
| PALOAK LIMITED | SC069075 | 21/02/1997 | 13/02/2004 | One Red Flag |
| ROCKROSE UKCS 10 LIMITED | 04105025 | 06/11/2000 | 13/02/2004 | Silver |
| ROCKROSE UKCS 9 LIMITED | 01293052 | 01/12/2000 | 13/02/2004 | Gold |
| SIGMA 3 (NORTH SEA) LIMITED | SC224630 | 19/05/2004 | 27/01/2005 | Dissolved |
| THE INDUSTRY TECHNOLOGY FACILITATOR | SC171891 | 24/08/1999 | 16/04/2002 | Dissolved |
| THE SCOTTISH ENERGY FORUM | SC414903 | 01/11/2012 | 12/12/2022 | Silver |
| WOOD GROUP ENGINEERING & OPERATIONS SUPPORT LIMITED | SC159149 | 19/05/2004 | 30/12/2011 | Bronze |
| WOOD GROUP ENGINEERING (NORTH SEA) LIMITED | SC030715 | 19/05/2004 | 14/04/2009 | Gold |
| WOOD GROUP ENGINEERING INTERNATIONAL LIMITED | SC247871 | 19/05/2004 | 30/12/2011 | Dissolved |
| WOOD GROUP HOLDINGS (INTERNATIONAL) LIMITED | SC169712 | 19/05/2004 | 30/06/2012 | Amber |
| WOOD GROUP MANAGEMENT SERVICES LIMITED | SC178510 | 19/05/2004 | 30/06/2012 | Dissolved |