Affiliated Managers Group announced Tuesday that Sean Healey, the Boston-based company’s president and chief executive officer, will succeed William Nutt as chairman at the beginning of next year. Nutt will remain on the company’s board of directors.

AMG also reported Tuesday that its third quarter earnings per share increased 42.9% to $1.50 per share, while diluted earnings per share for the third quarter rose 62.5% to $0.65. For the quarter, net income rose 91% to $34 million from a year earlier and revenue increased 62.9% to $354.4 million.

Healey, 49, has worked for AMG since 1995 when AMG had a single affiliate and under $1 billion in assets under management. The company now has 27 affiliates and approximately $300 billion in assets under management. Healey has been its president and CEO since 2005 and has been a member of the the board of directors since 2001. 

“Sean’s leadership and vision as chief executive officer have positioned the company to achieve extraordinary growth and success over time,” said Harold Meyerman, AMG’s lead independent director. “Under his leadership, AMG has become a leading global asset management company with a diverse set of outstanding products, particularly in fast-growing areas such as global and emerging markets equities and alternative investments.”

Before joining AMG, Healey was a vice president in the mergers and acquisitions department at Goldman Sachs.

Net client cash flows for the third quarter were approximately $5.5 billion, with flows in the institutional, mutual fund, and high net worth channels of approximately $4.2 billion, $1.1 billion, and $0.2 billion, respectively.  The aggregate assets under management of AMG’s affiliated investment management firms were approximately $294 billion as of Sept. 30.

Healey described the quarter was “excellent.” “Our results reflect the successful execution of our growth strategy, including accretion from investments in new affiliates as well as the strong organic growth of our existing affiliates,” he said in a release. “Our affiliates continue to generate outstanding investment performance across an array of product areas, particularly in emerging markets and international equity and alternative products.”