| Alan Bennett | Director | 2 Feb 2004 | 28 Apr 2005 | British | 74 years |
| Alfred Roberts | Director | 13 Oct 1993 | 19 Sept 1997 | British | 81 years |
| Andrew Daryl Le Poidevin | 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 Jul 2016 | British | 58 years |
| Anne Garrhy | Secretary | 26 Nov 1998 | 4 Jan 1999 | British | - |
| Anthony Charles Henshaw | Director | 25 Apr 1996 | 26 Nov 1998 | British | 72 years |
| Anthony Charles Henshaw | Director | 6 Apr 1999 | 2 Feb 2004 | British | 72 years |
| Anthony David Gower-jones | Director | 25 Nov 2011 | 1 Jan 2014 | British | 71 years |
| Centrica Secretaries Limited | Corporate Secretary | 31 Jan 2001 | 31 Dec 2018 | United Kingdom | - |
| Christopher Martin Cox | Director | 1 Mar 2016 | 8 Dec 2017 | British | 65 years |
| Christopher Terence Bird | Director | 8 Feb 2010 | 16 Apr 2012 | British | 66 years |
| Colette Brigid Cohen | Director | 1 Jan 2014 | 30 Jun 2016 | Irish | 58 years |
| Craig Mccallum | Director | 16 Apr 2012 | 1 Jan 2014 | British | 58 years |
| David Clarke | Director | 15 Mar 1999 | 17 Sept 2003 | British | 73 years |
| David John Jackson | Director | 13 Oct 1993 | 1 Feb 1994 | British | 73 years |
| David John Jackson | Secretary | 13 Oct 1993 | 1 Feb 1994 | British | - |
| David Patrick Houghton | Director | 25 Apr 1996 | 8 Oct 1997 | British | 72 years |
| David Ross Wilson | Director | 5 Mar 2010 | 3 Oct 2013 | British | 65 years |
| Dennis Gareth Jones | Director | 1 Nov 2019 | 30 Aug 2024 | British | 61 years |
| Deryk Irving King | Director | 19 Mar 1998 | 29 Jun 1998 | British,canadian | 79 years |
| Fraser Dawson Weir | Director | 13 Jul 2016 | 31 May 2018 | British | 54 years |
| Gerald Martin Harrison | Director | 8 Dec 2017 | 24 Jun 2022 | British | 72 years |
| Girish Rajkumar Kabra | Director | 5 Aug 2022 | 13 Mar 2025 | British | 48 years |
| Graeme Stuart Collinson | Director | 13 Feb 2009 | 11 Nov 2011 | British | 70 years |
| Gregory Craig Mckenna | Director | 8 Feb 2010 | 1 Jan 2014 | British | 60 years |
| Hywel Rhys Richard John | Director | 16 Feb 1998 | 26 Nov 1998 | British | 63 years |
| Iain Douglas Bartholomew | Director | 8 Feb 2010 | 1 Jan 2014 | British | 68 years |
| Ian Grant Dawson | Director | 26 Nov 1998 | 15 Mar 1999 | British | 67 years |
| Ian Ritchie | Secretary | 26 Jul 1999 | 31 Jan 2001 | British | - |
| Instant Companies Limited | Corporate Nominee Director | 21 Sept 1993 | 13 Oct 1993 | United Kingdom | - |
| Jacob Shields Ulrich | Director | 26 Nov 1998 | 31 Jul 2008 | British | 73 years |
| John Leonard Rennocks | Director | 1 Feb 1994 | 15 Jul 1996 | British | 81 years |
| John Nicholas Shears | Director | 15 Mar 1999 | 1 Jan 2002 | British | 68 years |
| John Nicholas Shears | Director | 28 Apr 2005 | 8 Feb 2010 | British | 68 years |
| John Wilson Astrop | Director | 8 May 1997 | 26 Nov 1998 | British | 78 years |
| Jonathan Leslie Roger | Director | 8 Feb 2010 | 20 May 2013 | British | 57 years |
| Jonathan Richard Morgan | Director | 1 Feb 1994 | 26 Nov 1998 | British | 78 years |
| Kenneth Murray Robertson | Director | 1 Jan 2014 | 8 Dec 2017 | British | 66 years |
| Lucy Elizabeth Caldwell | Secretary | 4 Jan 1999 | 31 Jan 2001 | British | - |
| Mark Stephen Lappin | Director | 1 Jan 2014 | 13 Jul 2016 | British | 65 years |
| Mark Sydney Clare | Director | 26 Nov 1998 | 15 Mar 1999 | British | 69 years |
| Michael John Garstang | Director | 24 Oct 2001 | 30 Jun 2008 | British | 78 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 Martyn Tanner | Director | 13 Jul 2016 | 31 May 2018 | British | 53 years |
| Peter Cole | Director | 2 Feb 2004 | 27 Jan 2010 | British | 75 years |
| Peter Eric Kingston | Director | 30 Mar 1994 | 26 Nov 1998 | British | 83 years |
| Richard Martin Mew | Director | 15 May 2006 | 8 Feb 2010 | British | 70 years |
| Richard Ozsanlav | Director | 28 Feb 2014 | 5 Jun 2015 | British | 57 years |
| Rodney George Barber | Director | 23 Dec 1996 | 26 Nov 1998 | British | 80 years |
| Roy Andrew Lumsden | Director | 5 Jun 2015 | 14 Jul 2017 | British | 68 years |
| Rune Martinsen | Director | 1 Jun 2018 | 31 Dec 2018 | Norwegian | 61 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 | 29 Sept 2023 | 18 Jul 2025 | British | 55 years |
| Simon Richard Clark | Director | 28 Jun 2007 | 14 Jan 2011 | British | 62 years |
| Steinar Meland | Director | 13 Jul 2016 | 8 Dec 2017 | Norwegian | 58 years |
| Stephen John Kemp | Director | 5 Mar 2010 | 16 Apr 2012 | British | 60 years |
| Swift Incorporations Limited | Corporate Nominee Secretary | 21 Sept 1993 | 13 Oct 1993 | United Kingdom | - |
| Teresa Jane Furmston | Secretary | 4 Jan 1999 | 22 Feb 1999 | British | - |
| Vincent Mark Hanafin | Director | 31 Jul 2008 | 8 Feb 2010 | British | 67 years |
| William Evelyn Chevalier Gubbins | Secretary | 1 Feb 1994 | 26 Nov 1998 | British | - |