Microsoft (MSFT) is under a preliminary investigation by Switzerland's antitrust watchdog over whether its recent license fee increases may indicate an "unlawful restriction of competition," the regulator said Thursday.

The preliminary probe was prompted by complaints of "significant increases" in pricing from customers of Microsoft 365.

The investigation is aimed at determining "whether the observed fee increases may constitute indications of an unlawful restriction of competition" under the country's Cartel Act. If the assessment is confirmed, the agency said it could launch a full probe.

Microsoft did not immediately reply to MT Newswires' request for comment.