Berkshire had about 11m shares of Goldman Sachs as of September 30, compared with 12.6m three months earlier, according to a filing yesterday.
The stake in Wal-Mart fell to 56.2m shares from 60.4m. Mr Buffett agreed to buy aerospace-equipment maker Precision Castparts in August for more than $30bn (€27.8bn).
The billionaire told CNBC that he sold some stocks to help pay for the deal.
The biggest additions in the third quarter were previously disclosed: Berkshire announced in August a major increase in its Phillips 66 stake, and Mr Buffett’s company is the top holder of Kraft Heinz.
While Mr Buffett booked a $4.4bn gain tied to the combination of Kraft and Heinz in the quarter, some of his other large holdings have tumbled, causing Berkshire to rack up rare paper losses.
One of the recent laggards, American Express, still trades well above the average price Berkshire paid for the shares. Wal-Mart is closer to break-even.
But unrealised losses on Berkshire’s stake in IBM widened to $2bn as of September 30, or about 15% of what Buffett paid. He said he expects the shares to recover.