If Berkshire drops its stake under 10%, it will no longer have to file with the SEC for any changes in its Bank of America holding within two business days. Berkshire would have t

Warren Buffett's company Berkshire Hathaway has built one of the largest and most successful stock portfolios in the world. It's now worth more than $300 billion. It's a great endorsement to be in Berkshire's portfolio. But it can also attract some unwanted attention if Buffett and Berkshire start to sell a stock.

Buffett's Berkshire Hathaway, the biggest shareholder in BofA, has been trimming its stake in the U.S. lender, making total share sales since mid-July of nearly $7 billion. Berkshire holds a stake in Bank of America of about 11.1%, according to LSEG data. Moynihan said the market is absorbing Buffett's stock sale.