Luminous Capital Holdings LLC, an independent wealth adviser in Century City, on Friday announced that it was being acquired by San Francisco’s First Republic Bank.

Luminous Capital, which as of September 30 had wealth management assets of $5.5 billion, will become part of First Republic Investment Management Inc., a wholly-owned subsidiary.

Financial terms of the cash deal were not disclosed, but the two companies said that Luminous’ six partners of the firm will sign long-term employment contracts. The deal is expected to close by December 31.

Luminous has offices in Portola Valley near San Francisco in addition to Century City, and it operates in the same markets and segments as First Republic Investment Management. First Republic, a publicly held bank holding company, has $31 billion in assets.

“Luminous Capital is a perfect fit with First Republic, and we welcome the opportunity to work with a team of wealth managers and bankers who have such a stellar reputation,” Luminous Chief Executive Eric Harrison said in a statement.