Warren Buffett’s Berkshire Hathaway Inc. took advantage of a plunge in bank stocks to pile even further into his bet on financials, while trimming a giant stake in Apple Inc.

Berkshire spent the last half of the year snapping up more shares of banks and insurers, moves that made the company a major shareholder in four of the five largest U.S. banks.

The changes were disclosed in a 13-F regulatory filing detailing Berkshire’s U.S.-listed stock portfolio as of Dec. 31, which shrank $38 billion in the quarter to $183.1 billion amid a broad selloff in stocks.

The filing includes investments by Buffett and his portfolio managers Todd Combs and Ted Weschler, but does not say who bought and sold what. Investors monitor Berkshire’s quarterly filings for signs about where Buffett, Combs and Weschler see value. Stock prices often move higher or lower when Berkshire discloses new stakes, or sheds old ones.

Among the stock moves highlighted in the company’s recent SEC filing, here are eight stocks the Oracle of Omaha is buying or selling.

The Omaha, Nebraska-based conglomerate boosted its stake or bought shares in:

1. JPMorgan Chase & Co.: Berskhire boosted its stake in JPMorgan Chase stock (JPM) 41 percent to 50.1 million shares, worth $4.9 billion.
2. Bank of America Corp.; Buffett first invested $5 billion in convertible BAC preferred stock in 2011. With the new shares he purchased in the fourth quarter, Berkshire’s Bank of America (BAC) stake is worth roughly $25.4 billion, USNews reported.
3. Canada’s Suncor Energy Inc.: Berkshire re-entered the stock (SU.TO), which it last owned in the third quarter of 2016, owning 10.76 million shares worth $300.9 million.
4. Software company Red Hat Inc.: Berkshire said it owned 4.18 million shares of Red Hat (RHT) worth $733.4 million.

Four stocks sold were:

1. Apple Inc.: Berkshire said it trimmed its stake in the iPhone maker (AAPL), though none of the selling was Buffett’s. Berkshire reduced its Apple stake by 1 percent in a period that marked its first holiday quarter sales decline in 18 years and saw shares plunge 30 percent. It’s still the biggest holding in Buffett’s portfolio, and the stock has rebounded 8 percent so far this year. Berkshire said in the filing that its Apple stake shrank to 249.6 million shares in the quarter from 252.5 million, reducing its reported stake to below $40 billion as Apple’s share price slid 30 percent. Buffett, though, had nothing to do with the selling. “One of the managers other than Warren had a position in Apple and sold part of it in order to make an unrelated purchase,” Buffett’s assistant Debbie Bosanek said in an email. “None of the shares under Warren’s direction have ever been sold.”
2. Oracle Corp. Berkshire also appeared to have shed a $2.13 billion stake in database software company Oracle (ORCL). after having first disclosed it in November. Berkshire’s dalliance with Oracle was short-lived. After taking a $2.1 billion stake in the software firm in the third quarter, Berkshire had sold out by year-end. Buffett has typically taken a more cautious approach to technology companies, given his lack of familiarity with the space. It is rare for Berkshire, which owns some stocks for decades, to unwind an investment so fast.
3. Wells Fargo & Co.: Berkshire sold about 15.5 million shares of WFC stock, trimming his holding by about 3.5 percent. Wells Fargo is still Berkshire’s third largest holding, valued at around $20.7 billion, USNews reported. 
4. United Continental Holdings: Berkshire holds stakes of Delta Air Lines (DAL), Southwest Airlines Co. (LUV) American Airlines Group (AAL) and United Continental (UAL), USNews reported. Buffett sold shares of both United and Southwest, but he was a more aggressive seller of United. Berkshire cut its United stake by 15.5 percent to about 21.9 million shares worth about $1.9 billion, the report said.

Berkshire has more than 90 businesses in the insurance, energy, food and retail, industrial, railroad and other sectors, and often buys stocks when buying whole companies appears too expensive. Its last major acquisition was in January 2016.

Material from Bloomberg and Reuters has been used in this report.

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