In an announcement to the market late Thursday, Kerr Neilson announced he would be stepping away from portfolio management to become a full-time executive director of Platinum Asset Management.
The board of the global fund manager has endorsed Mr Neilson's decision to hand over the chief executive role to Andrew Clifford, who co-founded the company in 1994.
As part of the changes from July 2018, Mr Neilson's portfolio management responsibilities will be divided between Mr Clifford and portfolio manager Clay Smolinski.
The announcement is part of a succession plan that began in 2013, when Mr Clifford took over the role of chief investment officer of Platinum.
In a letter to investors and shareholders, Mr Neilson said he held the positions of CIO and CEO concurrently before 2013 and found "my time was essentially focused on investing".
"More important still is that in an investment performance-driven organisation like Platinum, it is essential that the direction of the firm is controlled from the perspective of investing rather than from that of money gathering," he wrote.
According to a statement by Platinum company secretary Joanne Jefferies, Mr Neilson's new roles will include "continuing to work on the generation of investment ideas and company research".
Mr Neilson will also "provide additional support to Platinum's client diversification initiatives in Europe and the US", said the statement.
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