The Omaha, Nebraska, conglomerate bought nearly $1 billion of its own shares in August, the company disclosed in a securities filing on Monday after releasing its third-quarter earnings on Saturday.
Berkshire's Class B shares jumped more than 5 percent on Monday, leading the financial sector higher, on expectations that the buying may have continued into the final three months of the year. During October, Berkshire hit a high of $223 before falling to $198 and then rebounding. They closed trading on Monday up 4.68 percent, to $216.24.
The buying "sends a really strong signal to the market," said Edward D. Jones analyst Jim Shanahan.
Details from its filing show Berkshire was active buying other stocks between July and September as well. Net purchases of equities through the first nine months of the year were $24.4 billion, more than double the $11.8 billion net purchases reported through June. That means net purchases in the third quarter were about $12.5 billion.