Delta Air Lines (DAL) shares were up 2% in Monday's premarket activity after Berkshire Hathaway (BRK.A, BRK.B) disclosed a stake in the airline.
According to a regulatory filing, Berkshire Hathaway has acquired about 39.8 million shares of the US air carrier worth $2.65 billion.
Delta's market capitalization totals $46.14 billion.