The deal, announced Christmas, represents Berkshire's biggest acquisition outside the insurance industry, The Wall Street Journal reported. The Pritzker's have privately owned Marmon Holdings -- a collection of 125 transportation equipment units and electrical, construction and industrial components, including water treatment equipment and rail tank cars -- for more than 50 years.

Buffett is paying $4.5 billion for a majority share of Marmon and said he planned to purchase the remaining 40 percent of the company in phases over the next six years, the Journal said. The Pritzker family, who control the Global Hyatt Corp. hotel chain, TransUnion credit-reporting service and a large share in Royal Caribbean Cruises Ltd. (NYSE:RCL), have sold more than $10 billion in asset holdings since 2001.

Omaha's Berkshire Hathaway owns building products giant Johns Manville and other industrial sector companies.