Investors reacted to the surprise CEO exit by sending Fortescue’s shares 5 per cent lower to $19.75 in morning trade,which wiped about $3 billion off its value.

“The departure of Fiona has been both friendly and mutual,and we warmly wish her the best for her future,” Fortescue’s board said in statement. Forrest also recognised Hick’s contribution to the company. “We thank Fiona for her valuable efforts since joining Fortescue just under six months ago and wish her all the best with her future pursuits,” he said.

Hick said on LinkedIn that she valued her experience at Fortescue and thanked the company and its people for the opportunity. “I now look forward to time with family and friends while I consider my next move,” she said.

Multiple analysts with top-tier investment banks expressed concern about the instability in the company’s executive ranks. Goldman Sachs analyst Paul Young told Hutchinson and Otranto:“With respect to Fiona’s departure,I hear your explanation,but I do think shareholders deserve a better explanation seeing as she departed with only five months in the role,and also considering the C-suite changes in the past two or three years.”

Robert Stein from CLSA said:“One of the key advantages Fortescue has is operational capability and the ability … to drive cost improvements and productivity. It is a risk that such turnover[in executives] can start to erode that operational discipline.”

Otranto responded:“We’re still inherently very,very low in terms of our overall leadership turnover.”

Otranto said the company has performed strongly despite the executive turnover. “The reporting of executive turnover started 18 months,two years ago,and we haven’t missed a beat,” he said.

Hick,who had proven operational experience in highly complex energy and mining projects at both Woodside and Rio Tinto before being lured to run Fortescue,began in the role in February. Shetook over from Elizabeth Gaines,who stepped down as chief executive in August last year.

Fortescue is undergoing an ambitious transformation from an iron ore miner to a green hydrogen and clean energy company. The company is on an accelerated pathway to achieve net zero emissions by 2030,spending big on renewables and alternative energy sources.

Fortescue cut its final dividend to $1,taking its full-year dividend to $1.75 per share,which equates to $5.4 billion or a 65 per cent payout of underlying net profit. The company has given guidance of $US800 million ($1.2 billion) in net operating expenditure and $US400 million ($620 million) in capital expenditure for the 2024 financial year,which includes operating expenditure incurred for decarbonisation.

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