Investec has reached an agreement with Evolution to purchase the Williams de Broë owner in a deal worth £233m.
The deal puts a 100.24p value on each Evolution share, a premium of around 45% to the company's average closing mid-market price for the three months to 2 August.
Investec had faced competition for the purchase from Canaccord Genuity, but the latter withdrew from discussions with Evolution, which is comprised of Williams de Broe and broking arm Evolution Securities, earlier this week.
Last month Williams de Broe announced separate plans to acquire BNP Paribas Private Investment Management and its £1.8bn of asset under management.
Evolution chief executive Alex Snow said Williams de Broe would be able to"maintain its growth and continue to provide its clients with a best in class independent wealth management service" as a result of the deal".
"The group has seen strong growth in third party assets under management and the acquisition of Evolution will add further momentum," said Investec chief executive Stephen Koseff.
"The transaction strengthens our position in the UK, giving us greater scale in both private client wealth management and investment banking."
"Investec has built a strong platform in the UK and we expect the businesses we are acquiring to thrive as part of the group," said Bernard Kantor, managing director of Investec.
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