Sorrell's S4 Capital Is Bidding Against BlueFocus to Acquire Programmatic Buying Firm MightyHive

R3 estimates the deal at between $150 and $200 million

Martin Sorrell’s S4 Capital is in the throes of a bidding war to acquire MightyHive, which claims to be “one of the largest and fastest-growing programmatic buyers in the world,” with interested parties including China’s data technology company BlueFocus, according to sources familiar with the process.