Warren Buffett's Berkshire makes bet on U.S. airlines

Warren Buffett's Berkshire Hathaway Inc on Monday said it has bought shares in the four biggest U.S. airlines: American Airlines Group Inc , Delta Air Lines Inc , Southwest Airlines Co and United Continental Holdings Inc . In a regulatory filing, Berkshire said it owned $797 million of American, $249.3 million of Delta and $237.8 million of United shares, as of Sept. 30. Buffett told CNBC television that Berkshire has also invested in Southwest.