Why it matters: A primary concern surrounding Microsoft's acquisition of Activision Blizzard is the potential effect of making Call of Duty exclusive to Xbox and Windows. Sony recently expressed those fears to Brazil's competition regulator. The company's comments illuminate what it thinks truly makes a AAA game.

Sony has voiced its apprehensions over the Microsoft Activision deal to Brazil's Administrative Council for Economic Defense (CADE), one of many competition regulators from across the globe scrutinizing the purchase for anti-competitive behavior. If Activision stopped releasing Call of Duty games for PlayStation, Sony doesn't think it could replace the franchise with its own game.

Microsoft's agreement to buy Activision Blizzard – the biggest of its recent acquisitions – faces review from the American Federal Trade Commission, the UK's Competition and Markets Authority, and over a dozen other regulators in countries like Japan, Australia, New Zealand, China, South Korea, and Brazil.

Brazil's CADE makes the information from its investigations publicly accessible, including interviews with various game companies about how acquisitions might affect the whole industry. The documents are in Brazilian Portuguese, but a Resetera poster claiming to be an IT lawyer offered a summarized translation.

Sony told the CADE that while AAA games on Call of Duty's production scale can come from a few other companies such as itself, EA, Take-Two, or Epic Games, none of them could replicate Call of Duty. The PlayStation maker thinks Call of Duty's fanbase is so entrenched that even if another publisher made a similar game, it couldn't reproduce the Call of Duty brand.

Sony also thinks an exclusive Call of Duty would affect customers' console choice. The company admits the series is one of the largest sources of revenue from third-party publishers on PlayStation but redacts the exact numbers, so it isn't clear how much money Sony could lose if it lost Call of Duty.

Microsoft pledged that any currently-in-development multiplatform Activision Blizzard projects would remain so upon release. That includes Call of Duty: Modern Warfare II -- launching on October 28 -- Warzone 2, Diablo 4, and other upcoming games. This is unsurprising, as other significant Microsoft acquisitions like Minecraft still support non-Microsoft platforms.

In February, Microsoft said it won't necessarily keep future projects exclusive to Xbox and Windows either, including Call of Duty. This week, it reiterated that sentiment to New Zealand's competition regulator. However, it stated that none of Activision Blizzard's franchises would be irreplaceable were they to leave the platforms of Microsoft's competitors.

In addition to the warning from Sony, the CADE received responses from companies including Warner Bros., Ubisoft, Nuuvem, Bandai Namco, Apple, Riot Games, Amazon, Google, and Meta regarding Microsoft's acquisition. Google thinks Activision Blizzard games like Call of Duty and World of Warcraft are replaceable, citing Battlefield and Lost Ark as respective rivals, and Riot agrees. These companies also shared their opinions on what comprises the game market and in what capacity PC, console, and mobile compete.

The Microsoft-Activision Blizzard deal could receive approval as soon as August.