Berkshire Hathaway Inc., billionaire Warren Buffett's investment company, disclosed stakes in ConocoPhillips, General Electric Co. and United Parcel Service Inc. as part of regulatory filings detailing the company's $45.8 billion stock portfolio.
The documents filed with the Securities and Exchange Commission Monday are the first to mention Berkshire's holdings in ConocoPhillips because Berkshire had sought confidential status for its investment in the company, which was initiated last year.
Berkshire held 9.6 million shares of ConocoPhillips, worth about $559 million, on Dec. 31. Omaha-based Berkshire nearly doubled that investment by March 31 when it held 17.9 million shares worth about $1.1 billion.
Buffett's company often asks the SEC for permission not to disclose information that could hurt its trading strategy because the market likes to follow what the so-called "Oracle of Omaha" does. The SEC has begun rejecting those requests.
Berkshire's GE and UPS investments were made during the first quarter of this year. As of March 31, the company held 7.8 million shares of GE worth about $270 million and 1.43 million shares of UPS worth about $113.5 million.
Berkshire Hathaway spokeswoman Debbie Bosanek said no one was available Monday to comment.
This latest filing also revealed several changes in Berkshire's other stock holdings.
Berkshire added 3.3 million shares of Wells Fargo & Co. to the 56.4 million shares it already held.
Berkshire also added 564,800 shares of the American Standard Companies to the 10.5 million shares it held in December.
Buffett's company sold some of its shares in H&R Block Inc., Home Depot Inc., Iron Mountain Inc., Lexmark International Inc., Sealed Air Corp. and the Servicemaster Co.
Berkshire Hathaway owns businesses and stock in a wide variety of industries, including insurance, furniture, restaurants, candy and newspapers.