Microsoft has issued a subpoena to Sony Interactive Entertainment as part of its preparations for facing the Federal Trade Commission in court this summer.

A new filing in the case reveals the Xbox firm served the subpoena on Tuesday, January 17 with an initial response deadline of Friday, January 20.

However, on that day Sony requested an extension to Friday, January 27, which is expected to be granted.

Full details of the subpoena are not available, but the filing mentions that Microsoft and Sony are in ongoing negotiations as to what information the latter will provide. It appears to centre around Sony’s production capabilities, which presumably ties in to Microsoft’s defence against the FTC.

Microsoft is currently in the fact discovery stage of preparing its defence. The company has until April 7 to gather the information it needs, ahead of the hearing before an administrative judge at the FTC on August 2.

These legal proceedings follow the FTC issuing a legal complaint against Microsoft’s proposed acquisition of Activision Blizzard, the strongest attempt so far to block the deal.

Given that Sony and Microsoft are rivals in the console space, and Sony has repeatedly objected to the acquisition, the platform holder will be reluctant to share details on certain aspects of its production but the negotiations are designed to nail down what the company is willing to disclose.

You can catch-up on the regulatory hurdles Microsoft and Activision Blizzard face in our extensive primer.