Berkshire Hathaway, under the direction of Warren Buffett, has significantly increased its stake in Occidental Petroleum, now holding almost 29% of the company. This move follows years of collaboration between Berkshire and Occidental, leading to regulatory approval for Berkshire to purchase up to 50% of the firm. Buffett, known for investments in companies like Apple and Coca-Cola, became interested in Occidental after closely analyzing its earnings call, highlighting its unique attributes in the energy sector. While Berkshire has reduced its stake in other companies like Chevron and BYD, its interest in Occidental may not symbolize a broader strategy towards the energy sector. Occidental, led by CEO Vicki Hollub, has differentiated itself by investing in carbon capture technology. Despite the potential benefits, analysts have noted challenges facing Occidental, including lower oil prices and delays in acquiring CrownRock. Buffett's pursuit of Occidental is driven by diversification and opportunities within his vast portfolio.