
Berkshire Hathaway (BRK.B) recently reported on a 13-F filing that it had raised its stake in Occidental Petroleum Corp. (OXY). It now owns over 25% of OXY's shares, including warrants to buy at $59.624 per share.
For example, Buffett's company reported on Aug. 13 that it had bought 13.179 million shares. That brought its total to 224.129 million shares, which apparently includes 83.858848 million warrants allowing Berkshire to buy shares at $59.624 per share.