One of Warren Buffett's favorite rules of investing is that the lower prices get, the more he's likely to buy.
We now have another indication Berkshire Hathaway was indeed doing more buying as stock prices plunged in the third quarter.
According to Bloomberg's analysis, the latest quarterly SEC filing from Berkshire shows the company investing $23.9 billion in the quarter, the most in at least 15 years.
Bloomberg says that includes almost $7 billion in equity securities, up from $3.61 billion in Q2 and just $834 million in the first quarter.
Bloomberg notes that in mid-August Buffett told Charlie Rose that Berkshire had spent more on stocks on August 8 than any other day this year. That's the day stocks fell more than 6 percent in the wake of Standard & Poor's decision to downgrade the U.S. government's credit rating from AAA.
In a live interview on CNBC on September 30, Buffett told Andrew Ross Sorkin:
"We've bought, in the last quarter, the third— in the current quarter, we bought net 4 billion of common equities, which was similar to the total amount we bought in the first half. The cheaper stocks get, the better I like to buy them, whether it's our stock or somebody else's."
We'll get some more precise numbers a week from today, when Berkshire releases its end-of-Q3 "snapshot" of its portfolio of U.S. publicly traded equities.
And remember that for the previous two quarterly reports, Berkshire has received the SEC's permission to keep some of its holdings confidential, which could be a sign it's been building a position or positions and wanted to keep copycat buyers away for awhile.
Current Berkshire stock prices:
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