One of the longtime heads of Freddie Mac’s multifamily division is bolting for the private sector.

Mike McRoberts, Freddie Mac’s national head of sales and production, will be joining Newark, N.J.-based Prudential Mortgage Capital as managing director of its market-rate Fannie Mae and Freddie Mac business line on December 5. He’ll be based in Prudential’s McLean, Va., office, not far from his former stomping grounds.

The move underscores the brain drain that has taken place at the government-sponsored enterprises (GSEs) since being seized by the government in September 2008. In July, Freddie Mac lost its head of multifamily, Mike May, and last year, Freddie’s head of multifamily loan production, Mitch Kiffe, joined CBRE.

Freddie Mac has also lost less visible but vital positions, including many regional directors who left the company this year. A company spokesman said that it is looking internally and externally for McRoberts’ replacement.

“In his 19 years at Freddie Mac, Mike has proven himself to be a capable leader, who knows the business well and has great credibility with customers and in the industry,” said David Brickman, Freddie Mac’s senior vice president of multifamily, in an e-mail to customers Oct. 19. “I thank Mike for the remarkable combination of drive and professionalism he has brought to Freddie Mac and to our business. He will be greatly missed, and we wish him all the best.”

McRoberts was named head of multifamily production in May of last year. Before that, he served as national head of underwriting and credit, and prior, was the Southeast Regional director. He joined the firm in 1992.

Prudential has been a top agency lender for years. Last year, it was the eighth most active Fannie Mae lender, originating about $913 million. But it was just the 12th most active Freddie Mac lender in 2010, originating about $346 million. It did place first as the top FHA originator last year, totaling more than $2 billion, according to the Mortgage Bankers Association.