Robin Milway is exiting Neptune Investment Management after 10 months at the firm, representing the third manager change to the US Opportunities fund in 18 months.
Milway joined from EFG in September, but will “pursue other opportunities”, Neptune said in a statement.
Following his departure Ali Unwin, who runs the £10m Global Technology fund, becomes lead manager alongside co-manager Patrick Close.
In a statement, Neptune says technology is becoming an increasingly important area for active managers to understand.
James Hackman was also a manager on the US Opportunities fund, when Milway joined, but has since left. Hackman had taken over from Felix White in May last year.
Chief executive Robin Geffen says: “Neptune believes that the next decade will see a highly-significant process of disruption within stock market indices, driven principally by advances in technology.
“As head of technology at Neptune and manager of the Neptune Global Technology Fund, Ali is in prime position to identify these trends and carefully select the winning and losing companies, which will be absolutely vital to generate outperformance in the notoriously difficult-to-beat US market in the coming years.
“A deep understanding of the impact of technology on the economy and companies is a crucial tool for active managers.”
Unwin adds: “I truly believe that no investment sector or industry will be safe from technological disruption in the years to come.
“We have already seen major disruption to a considerable number of companies in recent years, and we believe that this is the beginning of a major structural shift to a digital economy, rather than a cyclical upswing.
“It is not merely that tech is the largest sector in the S&P – it is the pervasive role that technology is playing in every sector that is so important for active managers to understand.”
Unwin’s Global Technology Fund has returned 47.8 per cent since it launched in December 2015, compared to 46.9 per cent from the IA Technology & Telecoms sector.