UPDATE 2-Berkshire cuts Anheuser stake; adds NRG Energy

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By Jonathan Stempel

NEW YORK, Aug 14 (Reuters) - Berkshire Hathaway Inc (BRKa.N) (BRKb.N), the insurance and investment company controlled by Warren Buffett, sold some of its stake in Anheuser-Busch Cos before the brewer agreed to a $52 billion takeover by Belgium-based rival InBev NV INTB.BR.

In a Thursday filing with the U.S. Securities and Exchange Commission, Berkshire also reported a new 3.24 million share stake worth $138.9 million as of June 30 in independent Texas power generator NRG Energy Inc (NRG.N).

It also said it raised its stake in French drugmaker Sanofi-Aventis SA (SASY.PA) to 3.9 million American depositary receipts from 3.59 million three months earlier.

Berkshire also made a confidential filing with the SEC regarding its stake in the oil company ConocoPhillips (COP.N). It reported a 17.51 million share stake three months earlier.

The SEC regularly lets Buffett delay disclosing some of his investing activity so others cannot copy him. Berkshire bought $3.98 billion of stock in the quarter, another filing shows.

Berkshire's reported stock holdings on U.S. exchanges fell 12.9 percent to $57.88 billion as of June 30 from $66.46 billion three months earlier. The value of its overall equity holdings, including on non-U.S. exchanges, fell 4.2 percent over that time to $69.51 billion.

"He may have taken a bath on some holdings, which isn't inconsistent with the decline in the market," said Frank Betz, a principal at Carret/Zane Capital Management LLP in Warren, New Jersey, which owns Berkshire stock. "No one can outperform the indices consistently, especially an 800-pound gorilla like Berkshire."