Sanjiv Somani had been on the top job at Nutmeg for under a year.
A Companies House filing stated CEO Somani resigned as a director at both businesses on 6 August 2023. He was appointed on 16 November 2022.
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Nutmeg was bought by JP Morgan Chase in June 2021. It posted a £15m loss for 2020 and a £19m loss in 2021.
It is understood that Sanoke Viswanathan, who heads up JP Morgan's International Consumer Banking division in London, will oversee Nutmeg going forward.
JP Morgan declined to comment on the exit.
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