Hedge fund billionaire John Paulson's firm took a stake in Citigroup
Paulson, whose firm Paulson & Co bet against financial companies and the housing market before the credit crisis, also dissolved his stakes in Petro-Canada, Humana Inc
Besides Bank of America, Paulson cut his stake in JPMorgan Chase & Co
Investors scrutinize Paulson & Co's holdings since the firm reaped big gains by betting that the U.S. mortgage market would collapse in 2007. It also bet that financial services companies would tumble last year.
(Reporting by Robert MacMillan; editing by Carol Bishopric)