A Grok spokesman said it will engage directly with AGL’s 150,000 shareholders in the lead up to the AGM to explain the need for these candidates to “undertake the monumental amount of work required by the board”.

The endorsement of Twidell for a board role is not enough for the activist investor who said on Friday that the incumbent directors do not have the breadth of skills required to execute on this transition.

“It makes no sense to us – or a growing list of shareholders – that the board is rejecting highly qualified,independent directors who are committed to helping them make AGL the leading green gentailer in the world,” Grok said.

McKenzie said the AGL board respects the rights of shareholders to nominate candidates but repeated that it would be unusual for a noncontrolling shareholder to nominate four candidates for the board.

Cannon-Brookes’ Grok,and like-minded industry funds group - HESTA,UK investor outfit Martin Currie,Brookfield,Van Eck and a coalition of smaller activist investors - account for 19 per cent of AGL’s outstanding shares.

This week,another investor - high-profile fund manager Geoff Wilson - also called for the board to support the Grok candidates and rejected suggestions they would not be independent.

McKenzie said the skills of the rejected candidates were not needed.

“Given the depth of energy market and transition experience already represented on the renewed AGL board,the board is of the view that appointing all four of the Grok candidates would not add to the overall effectiveness of the board,” she said in a separate letter to AGL shareholders.

She also said the limit of ten directors for the board means that appointing all of Grok’s candidates could limit the board’s ability to bring on additional directors with other areas of expertise. If the candidates supported by the AGL board are elected,it will have 6 directors.

McKenzie was appointed as the board’s chair last month. She replaced Peter Botten who resigned after AGL’s long-held demerger plans were derailed by the campaign led by Cannon-Brookes.

AGL also announced at the time that the former chair of the Clean Energy Council,Miles George,would join the board. He is one of the new directors standing for re-election at the AGM,along with Graham Cockroft and Vanessa Sullivan.

McKenzie also faces re-election at the meeting.

The AGL board has experienced a purge over the last year with Botten,Graeme Hunt Jacqueline Hey and Diane Smith-Gander all departing after the failed demerger.

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