The UK's exit from the EU in 2021 empowered the UK Competition and Markets Authority (CMA) to probe big global mergers concurrently with the European Commission. So far, six acquisitions in digital markets have faced such parallel merger reviews. In five of them, both the acquirer and the target was a US-based company.
Our new report looks at these cases side by side, shedding light on the different conclusions often reached by the two authorities.
Stay tuned over the next weeks, as we look back at each case that saw divergent outcomes. Complimentary copies of detailed case summaries from Cullen International’s Antitrust & Mergers Database are available on request.

Case 2: Microsoft/Activision Blizzard
Microsoft’s $68.7bn (€63.9bn) acquisition of video game developer and publisher Activision Blizzard was by far the largest deal ever in the gaming industry as well as the largest acquisition ever made by one of the US big tech companies.
After their respective in-depth phase II merger investigations, the Commission and the CMA both concluded that the transaction would harm competition in the nascent cloud gaming market. The shared concern was that Microsoft could foreclose rivals by limiting their access to Activision’s popular video games.
However, the two authorities diverged on the remedy. While the Commission accepted Microsoft’s commitment to license Activision games royalty-free to cloud gaming providers for ten years, the CMA rejected the same remedy proposal and blocked the acquisition.
The CMA eventually cleared the transaction after an unusual move in which Microsoft re-notified a restructured deal, committing to divest Activision’s cloud streaming rights outside of the European Economic Area.
Subscribed clients can directly access our full coverage through the following links:
- Microsoft/Activision Blizzard EU case summary
- Microsoft/Activision Blizzard UK case summary
- Report on parallel merger reviews in the EU and UK
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