Warren Buffett speaks during the Berkshire Hathaway Annual Shareholders Meeting in Omaha, Nebraska on May 3, 2025.Warren Buffett's Berkshire Hathaway announced Thursday it reached a deal to buy Occidental Petroleum's petrochemical unit, OxyChem, for $9.7 billion in cash.The deal marks Berkshire's largest since 2022, when it paid$11.6 billion for insurer Alleghany. It also comes at a time in which the conglomerate is sitting on $344 billion in cash, a record for the company.Berkshire is already a major inve ...