Widdowson had built up a strong track record in charge of the trust, which seeks to use private equity techniques to invest in a concentrated portfolio of smaller company stocks. Over five years, the trust's shares have delivered around 170%.
'Stuart Widdowson's departure comes as a surprise to us as he had established a strong track record at Strategic Equity Capital via a differentiated approach to investing in UK smaller companies,' said analysts at Numis.
'It is not yet clear to us what the longer-term implications are for Strategic Equity Capital. We do not expect any changes to the investment approach, but Stuart was very much "the face" of the company with shareholders, and we can understand that investors will be cautious in the near term.'
Widdowson's record had led to shares in the trust enjoying a high rating, with a discount in single figures. While they stood at a 7.9% discount to net asset value before today's announcement, that discount has now widened, and could come under further pressure should Widdowson and his immediate family sell their stake worth around £1.3 million in the trust.
New manager Harris also serves as assistant manager to GVQ's two open-ended funds GVQ UK focus and GVQ Opportunities, headed by GVQ chief executive, Citywire A-rated Jamie Seaton.
GVQ UK Focus enjoys a strong long-term track record, up 98% over five years, placing it towards the top of the UK All Companies sector, although the younger GVQ Opportunities has returned a more muted 11.5% since its launch in October 2015.
Seaton said Harris and Khanbhai's promotions were 'well deserved'. 'They have both made significant contributions to the firm's strong investment performance, and I look forward to continuing to work with them and the team in building on the success of both GVQ and Strategic Equity Capital,' he said.
GVQ is owned by global investment trust RIT Capital Partners (RCP), which also holds a 14% stake in Strategic Equity Capital. RIT shares were flat at £18.47.
The author owns shares in Strategic Equity Capital.