In a stunning turn of events, the UK’s Competition and Markets Authority (CMA) has blocked Microsoft’s proposed acquisition of video game maker Activision Blizzard, a deal valued at $69 billion. This move has put a halt to what would have been the largest tech deal in history. The CMA’s final report expressed concerns that the merger could potentially suppress competition within the rapidly expanding cloud gaming market, particularly affecting popular franchises such as Call of Duty.

The proposed all-cash deal, announced over a year ago, has faced significant resistance from industry competitors such as Sony, the creator of the PlayStation gaming system. Regulators in both the U.S. and Europe have also been closely examining the deal amidst apprehensions that it could grant Microsoft and its Xbox console dominion over successful franchises like Call of Duty and World of Warcraft.

The companies involved in the deal have expressed their intent to appeal against the decision made by the UK watchdog. The CMA’s ruling has been described as surprising by many industry observers, including Liam Deane, a game industry analyst for research firm Omdia. The decision has further added to the global uncertainty surrounding the fate of this monumental tech deal.

The implications of this ruling extend beyond the companies directly involved. This move by the UK regulator underscores the growing scrutiny of mega mergers in the tech space and sets a precedent for future deals. As the landscape of the gaming industry continues to evolve, the outcome of this appeal will be closely watched by industry stakeholders around the globe.