Janus Capital Group Inc. announced Thursday it has hired Richard M. Weil as chief executive officer. Weil will replace Gary Black, who resigned suddenly in July as the Denver investment manager continued to suffer heavy outflows.

Black, who became the CEO of Janus in January 2006, resigned after several fund managers left following his switch to a more team-based investment strategy.

Weil, 46, currently the chief operating officer at Pacific Investment Management Co., will take the helm at Janus on Feb. 1. Since July, Janus has been run on an interim basis by Tim Armour, who is a director for the company.

Weil has worked for PIMCO for 13 years and most recently was its global head of PIMCO Advisory, a member of PIMCO’s executive committee, and a member of the board of trustees of the PIMCO Funds. He was chief operating officer for the past nine years. Weil also was a member of the Allianz Global Investors executive committee. PIMCO, a unit of Munich-based Allianz SE, had $940 billion of assets under management as of Sept. 30.

Before joining PIMCO in 1996, Weil worked for Bankers Trust Global Asset Management and the New York City-based law firm, Simpson Thacher & Bartlett LLP.

Steve Scheid, the chairman of Janus, said the board hired Weil after an extensive search and called Weil the perfect fit for the firm. “He is a proven leader with a strong vision for what makes a company and its people successful,” Scheid said. “The breadth of his leadership experience, deep understanding of the investment industry and global perspective were all key factors behind the board’s decision. These characteristics not only complement Janus’ key strengths, they also align with the firm’s long-term strategic priorities.”

In the first nine months of last year, Janus’ assets under management rose 22.9% to $151.8 billion, but since the end of 2007 assets have declined 26.6%. More than 90% of its assets are invested in equities. The company’s performance improved last year. Its funds outperformed 57% of similar funds last year, according to Morningstar Inc. And, its international equity funds beat 77% of comparable funds at rival firms, according to Morningstar.