In terms of international antitrust, friends in trouble are indeed friends. Increasingly aggressive merger controls in the US are retreating, paving the way for firewalls overseas. Now the US Federal Trade Commission (FTC) try to stop With Microsoft’s $69 billion deal to buy game developer Activision Blizzard, approaches will be more important than ever.

The FTC, led by competition advocate Lina Khan, moved earlier this month to block the software giant from acquiring the creators of World of Warcraft. file a complaint before an internal body court presided over by an administrative law judge. This path is considered more government-friendly, but the FTC has chosen a path that doesn’t include obtaining a federal court decision, meaning Microsoft can close the deal now.

The reason it won’t be is Europe. The FTC hearing is set for next August, but if the UK Competition and Markets Authority and the European Commission’s review is completed earlier, as expected, US regulators are empowered to seek a court decision.

This strategy is risky. Illumina DNA sequencer completed its $7.1 billion acquisition of biotechnology company Grail after the FTC did the same, rather than waiting for a European review. US antitrust officials circumvented the blockade, leaving any hope of intervention in the hands of their transatlantic counterparts. This part of the playbook has worked before: Britain torpedoed travel technology company Saber’s takeover of Farelogix, which US authorities tried unsuccessfully to stop in 2020.

Europe’s competition watchdog is also open to options that have been ruled out by the FTC. Microsoft has offered so-called concessions of conduct to allay concerns: that is, pledging to adhere to certain standards of behavior, rather than selling assets.

The FTC found such a settlement unacceptable, though the one offered in this case – for Microsoft to guarantee competitors access to Activision’s games for a decade – was at the heart of the concerns.

Brussels Head of Competition Margrethe Vestager is more willing to accept behavior-based solutions, and could get broader promises from Microsoft when the FTC rolls out an outright ban. In this way, multiple revisions can serve as reinforcement, guaranteeing a certain level of protection. In other words, Khan’s European counterparts could give him the freedom to challenge big technology.

The authors are columnists for Reuters Breakingviews. Opinion is yours. Translation, from Carlos Gomes Downit is the responsibility of Five days