(Reuters) - Warren Buffett's Berkshire Hathaway Inc on Thursday disclosed a new $3.45 billion stake in Exxon Mobil Corp, after buying 40.1 million shares in the world's largest publicly traded oil company.
The purchase was disclosed in a U.S. Securities and Exchange Commission filing that detailed Berkshire equity investments, mostly listed on U.S. exchanges, as of September 30.
Berkshire also disclosed other changes to its holdings, including a reduced stake in another oil company, ConocoPhillips.
U.S. regulators require large investors to disclose their stock holdings every quarter, and the disclosures can offer a window into their strategies for buying and selling stocks.
(Reporting by Luciana Lopez and Jonathan Stempel in New York; Editing by Gary Hill)