Coombs wants to reduce his holding to ‘more manageable’ level over the medium term, said Ashmore. Sales will be limited to a maximum of 4% of his stake each year.
A Cambridge law graduate, Coombs set up Ashmore as a new division of Australian bank AZN back in 1998, before leading a lucrative management buyout the following year.
The notoriously private 58-year-old, became a billionaire and one of the richest men in the Square Mile when he took the fund manager public in 2006.
Since then, he has continued to build up a list of blue-chip clients which has allowed Ashmore’s funds under management to surge to north of US$73bn from just US$500mln when it was first set up.
At its peak this time last year, the fund house was worth £3.3bn.
That growth has allowed the Tory party donor, who has lived down the same tree-lined street in Wimbledon for more than two decades, to pocket hundreds of millions in dividends over the years, including an estimated £45mln pay-out last September.
Shares in the fund manager eased 5% to 395p on news of Coombs' plans. but that still values his holding at £1.15bn.
Ashmore also revealed a solid half-year in spite of increased volatility in emerging markets.
Growing trade tension between the US and China, US economic data and economic collapses in Argentina and Turkey all hit the space, said the fund manager.
Net management fee income rose by 18% while underlying profits were 8% higher at £98.8mln.
Ashmore also indicated conditions had improved a little.
“The temporary factors that supported the US dollar in 2018 are fading and consequently Emerging Markets assets are performing strongly,” said Coombs.
Assets under management rose to 4% to US$73.9bn over the six months to December while there were net inflows of US$2.4bn.
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