Microsoft Deal Is a Tough Target for Trustbusters: Chris Hughes (2)

The UK is taking on a tough target in challenging Microsoft Corp.’s $69 billion acquisition of video-game publisher Activision Blizzard Inc.

While US and European regulators have yet to opine on the transaction, competition watchdogs are generally becoming more interventionist — especially in the case of tech giants. This deal offers a possible high-profile scalp.

Enter the UK Competition & Markets Authority. The agency concluded earlier this month that the combination poses a “realistic” threat to competition, setting the stage for a deeper probe. If this next investigation — confirmed on Thursday — crosses the higher threshold of demonstrating that harm is “likely,” the chance ...