National Mortgage News reports today that Fannie Mae is looking to acquire Credit-Based Asset Servicing and Securitization (C-BASS), recently hit by more than $1 billion in write-downs by owners MGIC and Radian. The alleged deal would give Fannie Mae its own servicing shop — C-BASS affiliate Litton Loan Servicing, one of the nation’s largest subprime servicers. C-BASS also acquired Fieldstone Investment Corporation in July. “They’ve been working on this for at least two months,” an anonymous source told the publication, describing the potential move as being motivated by “charter creep.” Update: American Banker is reporting a slightly revised story that says C-BASS will unload Litton Loan Servicing — and that Fannie and Goldman Sachs are at the forefront of the bidding. Subscribers can read the full story. The story cites Diane Pendley from Fitch as saying that the servicer is “in an active bidding process,” and that C-Bass expects to close a deal for the servicer this month.