It was revealed back in late March that Xbox appeared to be getting close to approving the Activision Blizzard takeover in the UK, with the CMA explaining that it no longer had any concerns about Call of Duty and PlayStation.
As you might expect, Sony isn't very happy about that. In the company's response to the CMA, the decision was described as "surprising, unprecedented and irrational". Here's a sample from the intro and conclusion of the document:
"The CMA’s reversal of its position on its consoles theory of harm is surprising, unprecedented, and irrational. The Provisional Findings (“PFs”) assessed a significant body of evidence in the round to support its finding that Microsoft would have the ability and incentive to withhold Activision content, and that this would substantially lessen competition by foreclosing PlayStation."
"...In conclusion, SIE respectfully submits that the Addendum does not justify the CMA’s U-turn on the consoles theory of harm. The revised LTV model is vitiated by errors that bias the model to finding no incentive to Microsoft to foreclose. The Addendum jettisons, without sound reason, the PFs’ thorough analysis of other evidence establishing Microsoft’s incentives. And the Addendum’s partial foreclosure discussion is based on pure speculation, rather than evidence."
"To reach a robust decision, the CMA should revisit its analysis of Microsoft’s incentives and partial foreclosure, correcting for the errors identified in this paper."
The rest of the document goes into detail about why Sony believes the CMA has erroneously come to the decision that Xbox's takeover of Activision Blizzard won't harm the console market, offering 10 pages' worth of observations.
There's always the chance the CMA might reverse its decision, but it seems unlikely at this point. That said, Microsoft isn't over the line yet, as the UK regulator is still considering the takeover's impact on the cloud gaming market.
If you're interested in reading Sony's report, you'll find the full thing on the UK government website along with Microsoft's response to the findings - the latter of which were obviously welcomed!