The Phoenix Companies Inc. now is the sole owner of one of its major investment management affiliates.[@@]

The Hartford company has paid an undisclosed sum to buy a minority stake in Seneca Capital Management L.L.C., San Francisco, that was held by Gail Seneca. Gail Seneca was Seneca Capital’s founder, chief executive officer and chief investment officer.

Gail Seneca, a veteran of Wells Fargo & Company, San Francisco, and the old Chase Lincoln First Bank, Albany, N.Y., formed Seneca Capital in 1989. Seneca Capital now manages $12 billion in assets for institutions and wealthy families.

Gail Seneca will continue to work at Luminent Mortgage Capital Inc., San Francisco, a publicly traded real estate investment trust that manages some Seneca Capital assets, Phoenix says.

All Phoenix is saying about the terms of the deal is that the amount is not material to its financial statements.

Phoenix bought out Gail Seneca because it wants to own 100% of its investment management operations, according to Phoenix Chairman Dona Young.

Gaining 100% control over the asset management business “will go far in making it a growing, profitable contributor to Phoenix,” Young says in a statement about the deal.

Young has presided over other major changes to Phoenix, including the sale of the company’s broker-dealer operations.

Although Phoenix wants to own its investment management firms, the firms can continue to maintain their own identities and investment philosophies, Young says.

Gretchen Lash, chief executive and chief investment officer of Engemann Asset Management, Pasadena, Calif., a wholly owned subsidiary of Phoenix Investment Partners, the main Phoenix investment management unit that specializes in growth equity investments, will take over as chairman of Seneca Capital, Phoenix says. Lash also will continue to run Engemann.