Former Permira boss Sir Damon Buffini has built a 5% stake in Gresham House.
According to regulatory filing, Buffini built the position through two separate transactions in the last few days through his investment vehicle Saffie Investments.
The first one, dated 21 October, saw him buy 327,000 shares equalling a 3.2% stake in the business.
This was followed by a second purchase on 25 October of 192,500 shares, lifting Buffini's total interest to 5.1%.
At the same time the Helium Rising Stars fund managed by David Newton has cut its exposure in Gresham from more than 7% to less than 4%.
Other significant investors in Gresham include River & Mercantile, which controls just under 5%.
Buffini was in charge of Permira for more than a decade, before standing down in 2014.
Gresham House, a former 157-year-old investment trust, was reincarnated as an asset management business in June 2014.
This rebirth was overseen by SVG Investment Managers founder Tony Dalwood (pictured) and Michael Phillips, founded iimia Investment Group - a precursor to Miton Group.
Gresham runs around £400 million in assets. Full-year numbers from the firm releasesd at the end September showed a 254% jump in revenue from £482,000 in 2015 to £1.7 million.
Most recently Gresham has taken on the management of LMS Capital and unveiled a Strategic Public Equity fund.
It has also launched a Forestry fund following the acquisition of Aitchesse.
In an announcement on the London Stock Exchange this morning it said it has raised £15 million for the fund, which is targeting £50 million by the second half of 2017.