The firm announced the move today and said Mark Gregory would be Mr Buxton’s replacement, subject to regulatory approval.
Mr Buxton will remain with the business as head of UK equities and manager of the Merian UK Alpha Fund.
Today’s announcement followed the completion of the management buyout of the firm in June 2018 and rebranding last autumn.
Following what the firm described as “an orderly handover of responsibilities” Mr Buxton will step down from the business’s executive committee.
However, as a major shareholder, he will continue to be involved in the firm’s development via his position on its board.
Mark Gregory joined the firm’s board in October 2018 as independent non-executive director and has played an active role in developing its strategy since then.
He was said to have extensive experience in the financial services sector, including 19 years at Legal & General Group plc, with the last four years as its chief financial officer.
He is also a non-executive director at Direct Line Insurance Group plc.
He started his career in 1984 at PricewaterhouseCoopers and has a degree in maths and physics from King’s College London.
Supported by the executive committee, board and shareholders, he will be responsible for driving the growth of Merian Global Investors.
Mr Buxton said: “2018 was a momentous year for Merian Global Investors.
“With the management buyout and rebranding complete, I believe this is the appropriate time for me to hand over the CEO role.
“I am completely committed to the business and I will continue to be involved in its development, in my role on the board.
“Having known Mark for many years, I am absolutely convinced that he is the right person to take the business forward.
“My passion for investment is as strong as ever and I think there are some great opportunities in UK equities today.
“I will continue to seek undervalued and attractive businesses, while actively working with firms to improve corporate governance.
“I look forward to delivering long-term returns for our clients for many years to come.”
Sarah Bates, chair of the board, comments: “Working with Richard has been a real pleasure; his passion and energy for the business is truly commendable and he has been instrumental in building Merian Global Investors into a market-leading asset management business.
“While we will miss his leadership, I look forward to his continued contribution to the company.
“I’m delighted that Mark Gregory has accepted the position of CEO.
“He is hugely experienced and enthusiastic about the future of the business and I have every confidence that Merian Global Investors will continue to excel under his guidance.”
Mr Gregory said: “I have been incredibly impressed by the Merian Global Investors team’s enthusiasm for building a differentiated asset manager and I’m honoured to be taking on the role of CEO.
“Together with the talented executive committee, I am dedicated to delivering the business’s ambitious growth plans, while maintaining the special culture cultivated under Richard’s leadership.”