Royal London UK Mid-Cap Growth trust manager Leigh Himsworth is set to leave the firm in the autumn to join Gartmore.
Derek Mitchell, manager of the Royal London UK Special Situations trust, will assume Himsworth's UK Mid-Cap Growth vehicle.
Joining RLAM in April 2006, Himsworth's UK Mid-Cap Growth trust is ranked fourth out of 277 funds in the IMA UK All Companies sector over three years to 20 July, up 8.1% against an average 16.4% fall, according to Morningstar.
RLAM says as Himsworth will move in the autumn the firm will have considerable time to make a smooth management transition.
"With an average of 19 years' market experience, there is a considerable depth of knowledge within the RLAM equity team," RLAM says.
"All funds benefit from the input of this extensive experience and RLAM is confident that the skills of Derek and his colleagues will continue to deliver strong performance for investors in the fund."
Himsworth also runs the Scottish Life UK Mid Cap pension fund. RLAM says it is still discussing the future management of the fund.
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