Warren Buffett's Berkshire Hathaway Inc. was downgraded by Standard & Poor's Ratings Services Thursday after the credit rating agency changed the way it evaluates insurance companies.

American International Group Inc (NYSE:AIG) was once a lumbering financial giant, a veritable black box of unknowable risks.

Berkshire Hathaway Inc. (NYSE:BRK.A) Today, let's look at investing giant Warren Buffett. His Berkshire Hathaway Inc. (NYSE:BRK.A) company has increased its per-share book value by an annual average of 19.7% between 1965 and 2012, leaving the S&P ...

Berkshire Hathaway Inc. (NYSE:BRK.B) was in 66 hedge funds' portfolio at the end of the fourth quarter of 2012. BRK.B investors should pay attention to an increase in hedge fund interest in recent months.

Credit-rating agency Standard & Poor's on Thursday cut its rating on Berkshire Hathaway Inc , the insurance and industrial conglomerate controlled by billionaire investor Warren Buffett, one notch, citing the company's reliance on its insurance ...

Warren Buffett's Berkshire Hathaway Inc on Wednesday revealed a new investment in Chicago Bridge & Iron Co and said it has added to one of its largest equity holdings, Wells Fargo & Co.

Berkshire Hathaway Inc. (NYSE:BRK.A) is a large, highly diversified conglomerate. So if you want to own Berkshire Hathaway stock, it's crucial that you understand exactly how the company makes money.

Editor's Note: Related Tickers: Berkshire Hathaway Inc. (NYSE:BRK.B), Dell Inc. (NASDAQ:DELL), MGM Resorts International (NYSE:MGM), Apple Inc. (NASDAQ:AAPL), Goldman Sachs Group, Inc. (NYSE:GS), Herbalife Ltd.

Berkshire Hathaway Inc. (NYSE: BRK-A) and Warren Buffett released the conglomerate's stock holdings as of March 31, 2013.

New York, NY, United States (4E) - Standard & Poor's lowered Berkshire Hathaway Inc.'s credit rating by a notch to double-A, citing the company's dependence on its insurance business.