Berkshire Hathaway sold about 33.9 million shares of Bank of America for around $1.48 billion over multiple transactions this week, a regulatory filing showed.

After the sale, Berkshire owned about 999 million BofA shares.

Berkshire is one of the Charlotte, North Carolina-based lender’s largest shareholder. It also invests in several other banks, including Wells Fargo & Co (WFC.N), opens new tab and JPMorgan Chase (JPM.N), opens new tab

The conglomerate, owned by Warren Buffett, began investing in Bank of America in 2011, purchasing $5 billion of preferred stock plus warrants to buy 700 million common shares, at a time many investors worried about the bank’s capital needs.