Shares of JPMorgan were up 1.8% in trading after Buffett's Berkshire Hathaway Inc. (BRK.A) disclosed a new stake of 35.66 million shares, or 1.1% of all of the bank's outstanding shares.
Shares of Oracle rose 2.14% after Berkshire Hathaway bought 41 million shares of the software company worth $2.1 billion.
JPMorgan wasn't the only financial to get a boost from Buffett. According to 13-F filings, he also bought stakes in Wells Fargo & Co. (WFC) , PNC Financial Services Group Inc. (PNC) , insurer Travelers Cos. (TRV) , Goldman Sachs Group Inc. (GS) , Bank of America Corp. (BAC) and U.S. Bancorp (USB) .
Berkshire's bet on financials boosted the financial sector's share of the firm's portfolio to 42.59% from 40.5% in the previous quarter.
Outside of financials, Buffett also expanded his stake in Apple Inc. (AAPL) by 522,802 shares. Berkshire Hathaway now owns a little more than 5% of Apple's outstanding shares.
It wasn't all buys for Berkshire Hathaway in the quarter. The company ended its long-term investments in Sanofi SA (SNY) and Walmart Inc. (WMT) . It also shaved its position in Philips 66 (PSX) by half, and made slight reductions in its holdings in American Airlines Group Inc. (AAL) and United Continental Holdings Inc. (UAL) .