| Name | Company Number | Date Appointed | Rating |
|---|---|---|---|
| Hough,Thomas,& Co Ltd | 00757897 | 12/04/1996 | Dissolved |
| MITIAN LLP | OC351510 | 14/01/2010 | Dissolved |
| Proton Chemicals (London) Ltd | 01125544 | 11/01/2000 | Dissolved |
| Proton Chemicals (Northern) Ltd | 01504861 | 16/04/1991 | Dissolved |
| S & I Services Ltd | 03933188 | 13/09/2000 | Dissolved |
| Thomas Hough Servicing Division Ltd | 01511321 | 12/04/1996 | Dissolved |
| Name | Company Number | Date Appointed | Date Resigned | Rating |
|---|---|---|---|---|
| BYRON WALK MANAGEMENT COMPANY LIMITED | 00964967 | 16/03/2007 | 29/06/2020 | Gold |
| CHEMBLEND LIMITED | 01950729 | 16/04/1991 | 29/09/2006 | Dissolved |
| IBD CAPITAL LIMITED | 06524366 | 04/07/2008 | 05/06/2022 | Amber |
| LONDON AND POCKLINGTON LLP | OC339593 | 08/10/2008 | 01/01/2013 | Not Trading |
| PROTON CHEMICALS LIMITED | 02561742 | 23/11/1991 | 29/09/2006 | Dissolved |
| PROTON GROUP HOLDINGS LIMITED | 04901229 | 16/09/2003 | 29/09/2006 | Dissolved |
| SWC HEALTH AND HYGIENE LIMITED | 00822399 | 08/09/2000 | 29/09/2006 | Dissolved |
| THE PROTON GROUP LIMITED | 01000982 | 16/04/1991 | 29/09/2006 | Silver |