And then there were five.
Imperial Brands (IMB.L) said on Thursday that Alison Cooper — one of the exceedingly few women who lead FTSE 100 companies — will step down as CEO after nine years at the helm.
Her departure will bring an end to a 20-year career at the Bristol-based company, which is the fourth-largest tobacco company in the world.
Depending on when a successor is found, the FTSE 100 (^FTSE) index, which tracks Britain’s top 100 listed companies, could have only five female bosses until Alison Rose becomes CEO of the Royal Bank of Scotland Group (RBS.L) in November.
The top ranks of British business have struggled with gender equality: There are currently more men named Steve at the helm of companies on the index than there are women.
Cooper’s departure comes after Imperial Brands last week said that profits in its current financial year would be significantly lower than it had previously forecast, amid a crackdown on vaping in the US.
Shares in the company fell as much as 15%, hitting nine-year lows.
“The timing of the move is curious, given that the company as well as the sector is facing some serious headwinds as we move into the end of the year and look to 2020,” said Michael Hewson, the chief market analyst at CMC Markets.
“The tobacco industry is now facing the prospect of an existential crisis. With a slowdown on normal cigarette sales already cutting into profits, e-cigarettes were supposed to be the next key growth area,” said Hewson.
Since becoming CEO in May 2010, Cooper slashed the number of the company’s cigarette brands in half, focusing on quality over quantity.
She also oversaw the $7bn (£5.7bn) acquisition of several cigarette brands from US tobacco giant Lorillard in 2014.
Her departure comes amid a greater push for gender equality, with the government hoping that 33% of board members of listed companies will be female by next year.
But Cooper has previously spoken out against quotas, saying she was “very concerned” about addressing the issue this way.
“I am not someone who supports quotas because quotas are around the demand side of the equation and you need to look at the supply side. And quick fixes on the supply side are not necessarily quality fixes. I don’t like to think we’re a commodity,” she said.
Imperial Brands chairman Mark Williamson, who will also step down as chairman after a nine-year tenure, said that Cooper had made a “tremendous contribution” to the company.
“Alison has worked tirelessly and with great energy and passion during her 20 years with Imperial,” Williamson said.
The company said that Cooper would “focus on driving the performance of the business” while it searches for her successor.