Buffett Watch

Has Warren Buffett Been "Buying American" for Berkshire Hathaway?  We Find Out Today

Exactly four months ago today, on October 17, Warren Buffett wrote an op-ed piece for the New York Times with one of his rare, specific market calls for investors: "Buy American.  I Am."

He explained how falling stock prices had prompted him to pick up U.S. stocks at bargain prices .. for his personal account.

At that time he said, "If prices keep looking attractive, my non-Berkshire net worth will soon be 100 percent in United States equities."

If anything, prices became even more attractive after Buffett's op-ed.  The S&P closed at 940.55 on October 17.  Just over one month later, on November 20, it had fallen another 20 percent to its current bear-market closing low of 752.44.

Later today (Tuesday), we'll get the answer to a key question:  Was Buffett also buying U.S. stocks for Berkshire Hathaway's portfolio at the same time?

After the closing bell, Berkshire will file its portfolio "snapshot" taken at the end of the quarter, on December 31.

Berkshire's filing for the third quarter showed a big increase for its holdings of ConocoPhillips .

We also know that Berkshire has been loaning a lot of money to various companies, acting as a bank of last resort, and thus able to charge premium interest rates. 

(See Tiffany, Swiss Re, Harley-Davidson, Goldman Sachs, and General Electric.)

Some of the cash that might have been used to buy stocks for Berkshire has presumably been put to work by the Bank of Buffett.

Current Berkshire stock prices:

Class A:

Class B:

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Questions?  Comments?  Email me at buffettwatch@cnbc.com