Berkshire Hathaway shares rose on Monday, buoyed by strong operating results and a ramp-up in capital spending. The conglomerate's Class A shares advanced 2.3% in early trading.

Berkshire reported a 16% year-over-year increase in second-quarter operating profit, as robust performance from its energy and railroad businesses more than offset weakness in insurance underwriting. Under new CEO Greg Abel, the company has stepped up its deployment of a massive cash reserve, a move that has drawn investor enthusiasm. The company repurchased approximately $4.5 billion of its own stock during the quarter, a significant acceleration from the $235 million in buybacks in the first quarter. Berkshire also turned into a net buyer of stocks for the first time in 15 quarters, with total stock purchases outpacing sales by nearly $20 billion. As of the end of June, the company's cash pile fell to $365.5 billion, down from a record $397.4 billion three months earlier.