Neptune Investment Management's James Hackman has left the firm, just months after being appointed lead manager of the group's £285m US Opportunities fund.
Robin Milway has assumed the role of lead manager of the US Opportunities fund with Pat Close and Ali Unwin as deputy managers.
Meanwhile, George Boyd-Bowman, manager of the group's £8m Global Income fund, has been appointed lead manager of the £35m US Income fund, supported by co-manager and Neptune CEO Robin Geffen.
A statement from Neptune said: "While we are disappointed that James Hackman (pictured) has decided to pursue opportunities elsewhere, George Boyd-Bowman has established experience running dividend-growth focused mandates.
"As a manager of a global equity income fund George knows the US income market very well. A member of the team for over six years, George is a big talent and we have every faith he will carry on the good work James has done since taking over the fund in June 2014."
Hackman was appointed lead manager on the US Opportunities fund in May following the departure of Felix Wintle. He had run the US Income fund since June 2014, while Close was appointed lead manager of the US Mid Cap fund, which was launched in August.
Milway also joined in August as head of stock selection from EFG Private Bank. It was initially planned to launch a European fund but Neptune revealed earlier this week he had joined the US equity team.
At the time, Charlie Parker, head of distribution, told Investment Week: "Robin has a long track record across all asset classes and has run regional and global strategies.
"He previously was involved in the European fund at EFG, which had done very well, so the opportunity for us was to launch a fund.
"However, we feel Robin will have the most positive influence on stock selection by focusing on US equities, which covers half the global stockmarket."
Performance on the US Opportunities had already started to turn around under Hackman's leadership with the fund moving from fourth quartile over one, three and five years, to first quartile over three and six months.
Over the past three months to 26 September, the fund has returned 14.1% compared to the IA North America sector average of 12.3%, according to FE.
Meanwhile, Boyd-Bowman has been manager of the group's Global Income fund since 2012.
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