Occidental's stock price more than doubled in the first five months of this year, benefiting from the surge in crude prices fueled by Russia's invasion of Ukraine. However, the energy company's shares have slumped by 11% over the past month. Buffett and his team may have resumed buying because they saw the stock as a bargain again. Buffett's renewed interest in Occidental this year was sparked by CEO Vicki Hollub's comments during a February earnings call. She outlined her plans to optimize production, cut debt, raise dividends, restart stock buybacks, and maximize free cash flow over the long term. "What Vicki Hollub was saying made nothing but sense," Buffett gushed during Berkshire's annual shareholders' meeting in April. "I decided that it was a good place to put Berkshire's money," he said about Occidental.