| Alan Bennett | Director | 24 Oct 2001 | 28 Apr 2005 | British | 74 years |
| Andrew Daryl Le Podevin | Director | 19 Jan 2006 | 5 Oct 2011 | British | 68 years |
| Andrew Daryl Le Poidevin | Director | 14 Jul 2017 | 31 May 2019 | British | 68 years |
| Andrew Richard Bevington | Director | 1 Jan 2014 | 13 Feb 2017 | British | 58 years |
| Anne Garrihy | Secretary | 2 Feb 1996 | 8 Aug 1996 | British | - |
| Anthony David Gower-jones | Director | 25 Nov 2011 | 1 Jan 2014 | British | 71 years |
| Centrica Secretaries Limited | Corporate Secretary | 11 Sept 2000 | 31 Dec 2018 | United Kingdom | - |
| Christopher Martin Cox | Director | 1 Mar 2016 | 8 Dec 2017 | British | 65 years |
| Colette Brigid Cohen | Director | 1 Jan 2014 | 30 Jun 2016 | Irish | 58 years |
| David Clarke | Director | 16 Feb 1998 | 17 Sept 2003 | British | 73 years |
| Dennis Gareth Jones | Director | 13 Jan 2020 | 30 Aug 2024 | British | 61 years |
| Donald William John Patience | Secretary | 2 Feb 1996 | 8 Aug 1996 | British | - |
| Elizabeth Jayne Felton | Secretary | 30 Jan 1997 | 1 Oct 1997 | British | - |
| Gerald Martin Harrison | Director | 8 Dec 2017 | 24 Jun 2022 | British | 72 years |
| Graeme Stuart Collinson | Director | 13 Feb 2009 | 11 Nov 2011 | British | 70 years |
| Graham John Bartlett | Director | 30 Jan 1996 | 30 Aug 1996 | British | 70 years |
| Hackwood Directors Limited | Corporate Nominee Director | 18 Oct 1995 | 30 Jan 1996 | United Kingdom | - |
| Hackwood Secretaries Limited | Corporate Nominee Secretary | 18 Oct 1995 | 30 Jan 1996 | United Kingdom | - |
| Iain Douglas Bartholomew | Director | 16 Apr 2012 | 1 Jan 2014 | British | 68 years |
| Ian Ritchie | Secretary | 26 Jul 1999 | 11 Sept 2000 | British | - |
| Jacob Shields Ulrich | Director | 31 Oct 1997 | 31 Jul 2008 | British | 73 years |
| John Cowie | Director | 5 Aug 2022 | 7 Apr 2023 | British | 58 years |
| John Henry Jackson | Secretary | 30 Jan 1996 | 2 Feb 1996 | British | - |
| John Nicholas Shears | Director | 1 Mar 1997 | 5 Jan 2002 | British | 68 years |
| John Nicholas Shears | Director | 28 Apr 2005 | 8 Feb 2010 | British | 68 years |
| Jonathan Leslie Roger | Director | 8 Feb 2010 | 20 May 2013 | British | 57 years |
| Kenneth Murray Robertson | Director | 1 Jan 2014 | 8 Dec 2017 | British | 66 years |
| Lucy Elizabeth Caldwell | Secretary | 31 Oct 1997 | 11 Sept 2000 | British | - |
| Mark Stephen Lappin | Director | 1 Jan 2014 | 13 Jul 2016 | British | 65 years |
| Michael John Garstang | Director | 1 Aug 2001 | 30 Jun 2008 | British | 78 years |
| Michael Peter Astell | Director | 10 Dec 2010 | 15 Nov 2013 | British | 60 years |
| Michael Richard Alexander | Director | 30 Jan 1996 | 31 Oct 1997 | British | 79 years |
| Neil James Mcculloch | Director | 1 Jan 2019 | 29 Sept 2023 | British | 56 years |
| Nicholas James Dunn | Director | 28 Apr 2005 | 19 Jan 2006 | British | 60 years |
| Nicholas William Maddock | Director | 8 Feb 2010 | 5 Jul 2011 | British | 55 years |
| Nicola Jane Macleod | Director | 11 Sept 2018 | 31 Jul 2024 | British | 52 years |
| Nicola Macleod | Secretary | 29 Jan 2019 | 31 Jul 2024 | - | - |
| Paul De Leeuw | Director | 11 May 2011 | 16 Aug 2013 | British | 62 years |
| Paul Ian Hedley | Director | 1 Sept 2011 | 25 Oct 2013 | British | 57 years |
| Paul Joseph Massara | Director | 31 Oct 1997 | 16 Feb 1998 | British | 61 years |
| Paul Martyn Tanner | Director | 13 Jul 2016 | 31 May 2018 | British | 53 years |
| Paul William Ellis | Director | 30 Jan 1996 | 29 Nov 1996 | British | 80 years |
| Peter Julian Lehmann | Director | 19 Dec 1996 | 31 Dec 1998 | British | 82 years |
| Peter Kevin Cochrane | Director | 2 Feb 2004 | 2 Dec 2010 | British | 74 years |
| Richard Ozsanlav | Director | 28 Feb 2014 | 5 Jun 2015 | British | 57 years |
| Roy Andrew Lumsden | Director | 5 Jun 2015 | 14 Jul 2017 | British | 68 years |
| Sarwjit Sambhi | Director | 20 May 2013 | 29 Feb 2016 | British | 57 years |
| Sarwjit Sambhi | Director | 17 Sept 2003 | 28 Apr 2005 | British | 57 years |
| Scott Mcginigal | Director | 18 Sept 2024 | 18 Jul 2025 | British | 55 years |
| Simon Richard Clark | Director | 21 Mar 2003 | 2 Feb 2004 | British | 62 years |
| Steinar Meland | Director | 13 Jul 2016 | 8 Dec 2017 | Norwegian | 58 years |
| Stuart Ross | Director | 16 Jun 1997 | 31 Oct 1997 | British | 70 years |
| Tamsin Maureen Kathleen Lishman | Director | 13 Feb 2017 | 31 Dec 2018 | British | 50 years |
| Teresa Jane Furmston | Secretary | 1 Dec 1997 | 22 Feb 1999 | British | - |
| Vincent Mark Hanafin | Director | 31 Jul 2008 | 8 Feb 2010 | British | 67 years |