The European Commission (EC) opened an in-depth investigation into a proposed acquisition of game publisher Activision Blizzard by Microsoft, raising the prospect the deal could be delayed or derailed if deemed detrimental to competition.

In a statement, the EC cited Microsoft and Activision Blizzard’s respective positions in the gaming and software markets as the cause of concern over the impact of the deal on competition.

It cited the potential for Microsoft to use its position in the gaming software, hardware and cloud sectors to restrict rival console makers’ access to Activision Blizzard’s titles, which include the highly-successful Call of Duty series.

The European watchdog also expressed concern over the potential for Microsoft to negatively impact the PC operating system sector by discouraging users from purchasing machines not running its Windows system.

At this stage the EC emphasised the probe would evaluate if initial concerns raised by a preliminary investigation were warranted, with no final decisions taken at this point.

It has until 23 March 2023 to issue a ruling.

The EC probe adds to an ongoing investigation by the UK Competition and Markets Authority commenced in July which was moved to a second-stage in September, with a decision deadline of 1 March 2023.