Quarterly Form 13Fs provide investors with an under-the-hood look at which stocks Wall Street's prominent money managers -- including Warren Buffett -- have been buying and selling. Nearly half the stocks Buffett purchased during the first quarter are companies he considers "indefinite" holdings.

Warren Buffett’s Berkshire Hathaway Inc. slashed its exposure to big-bank shares in the first quarter, liquidating its position in Citigroup Inc. and trimming positions in Bank of America Corp. and Capital One Financial Corp., according to a regulatory filing on Thursday.