Miller, who had been in on a four month sabbatical, has been at the firm since it was founded by executive chairman John Duffield back in January 2001.
In a statement to the stock exchange, New Star announced that his departure was to “pursue other opportunities.”
Duffield saiys: “Alan joined as a friend and he leaves as a friend. We wish him good fortune in his future career.”
In addition to his role as CIO, Miller also had stints running the firm’s UK hedge fund and the UK growth vehicle. He was previously head of the specialist UK investment team at Jupiter Asset Management.
Miller says: “I have worked with John and many of his New Star team for more than a decade. I am confident that the business will continue to prosper.”