The blockbuster deal raises the odds that Buffett’s Berkshire Hathaway, which owns the Burlington Northern Santa Fe railroad, will reach a deal with CSX to create a second transcontinental railroad. Union Pacific and BNSF compete in the western U.S., while CSX and Norfolk Southern are the two big Eastern railroads.

Berkshire Hathaway is of course no stranger to this market. Geico, BNSF, and Fruit of the Loom were all publicly traded at one point. Berkshire made them private by wholly acquiring them. Adding more privately held companies and holding fewer publicly traded equities isn't exactly uncharted waters.

The Sage of Omaha's company will make over $1.2 billion from the sale, according to an announcement on Monday.

Acquiring CSX would be expensive for Berkshire, but it would still be accretive to its earnings, one analyst calculated.

BERKSHIRE Hathaway sold about one-third of its stake in VeriSign, an internet infrastructure and domain name registry company that Warren Buffett’s conglomerate has invested in since 2012, VeriSign said on Monday.