Warren Buffett's Berkshire Hathaway nears $1 trillion valuation; among rarefied list of American businesses

Berkshire Hathaway's market value nears $1 trillion. Limited investment opportunities affect share price growth. Berkshire faces potential lawsuit over 2020 wildfire costs. Buffett praises Charlie Munger and successor Greg Abel. Berkshire's operating profit increases due to underwriting and investment income.