Warren Buffett's Berkshire Hathaway (BRK-B, BRK-A) increased its stake in energy company Occidental Petroleum (OXY), buying an additional 763,000 shares on February 7 and bringing the firm's total ...

Occidental Petroleum (OXY) and Magnolia Oil & Gas (MGY) are falling 4% and 3%, respectively, after Goldman Sachs downgraded its ratings on the fossil fuel exploration firms. Why Goldman Downgraded ...