Warren Buffett plows another $337 million into Bank of America, boosting his stake to nearly 12%

• Warren Buffett spent another $337 million on Bank of America stock between July 31 and August 4, SEC filings show.
• The billionaire investor and Berkshire Hathaway CEO has splurged close to $2.1 billion on the bank's shares over the past 12 trading days, raising his ownership stake to almost 12%.
• Bank of America is the second-biggest holding in Berkshire's stock portfolio after Apple.
• Buffett has permission to boost his position as high as 24.9%, a banking regulator told Business Insider this week.
• Visit Business Insider's homepage for more stories.

Warren Buffett continued his Bank of America buying spree this week, spending another $337 million on the banking titan's shares between July 31 and August 4, Securities and Exchange Commission filings show.

The famed investor's Berkshire Hathaway conglomerate snapped up 13.6 million shares at an average price of around $24.81. As a result, its stake in the bank swelled to over 1.03 billion shares or 11.9% — a position worth close to $26 billion based on Bank of America's closing share price on Tuesday.

Buffett has now shelled out nearly $2.1 billion on 85 million of the bank's shares over the past 12 consecutive trading days. The purchases have boosted Berkshire's position by about 9%.

Read More: Vanguard is emerging as a key force in a $3.8 trillion battle against PIMCO and BlackRock for bond investors' cash. Meet 4 power players it brought on to help drive its push.

Berkshire is Bank of America's biggest shareholder, and Bank of America is the second-largest holding in Berkshire's stock portfolio after Apple.

Buffett has been granted special permission to more than double his Bank of America stake to 24.9%, a spokesperson for the Federal Reserve Bank of Richmond told Business Insider this week. Investors are typically allowed to own up to 10% of a bank.

The billionaire is probably bolstering his investment in Bank of America because its stock price is down about 30% this year, and he expects it to make a full recovery from the coronavirus pandemic in time.

Read More: Fund manager Tom O'Halloran quadrupled investors' money in 9 years by betting on super high-growth companies. He explains his approach, and why new technologies could make the next decade even more prosperous than the 2010s.

Here's a chart showing Buffett's spending on Bank of America stock in recent days: