The European Commission says it’s “concerned that Microsoft may be abusing and defending its market position in productivity software” by bundling Teams with Office 365 and Microsoft 365. (Microsoft Photo)

Microsoft is officially back on the European Commission’s investigative agenda.

European antitrust authorities opened a formal investigation Thursday into Microsoft’s bundling of Teams into Office 365 and Microsoft 365.

The move comes three years after Slack filed the complaint that formed the basis for the inquiry. That was in July 2020, at the height of the COVID-19 pandemic, when Teams and other communication and collaboration technologies, most notably Zoom, were soaring due to the sudden rise of remote work.

It has been nearly 14 years since Microsoft settled its last major European antitrust case, over the bundling of Internet Explorer with Windows 7.

In recent weeks, Microsoft and the European Commission were unable to agree on the specifics of a deal to unbundle Teams from Office 365 and Microsoft 365, according to a previous Financial Times report.

“In particular, the Commission is concerned that Microsoft may grant Teams a distribution advantage by not giving customers the choice on whether or not to include access to that product when they subscribe to their productivity suites and may have limited the interoperability between its productivity suites and competing offerings,” the commission said in a statement announcing the investigation.

A Microsoft spokesperson said in a statement, “We respect the European Commission’s work on this case and take our own responsibilities very seriously. We will continue to cooperate with the Commission and remain committed to finding solutions that will address its concerns.”

This is part of a major business for Microsoft. Office Commercial revenue grew 12% to $11.2 billion in Microsoft’s fiscal fourth quarter, representing nearly 20% of the company’s overall $56.2 billion in revenue for the period, according to GeekWire’s calculations from the company’s earnings report this week.

Several months after Slack filed its complaint, Salesforce reached a deal to acquire the San Francisco-based company for $27.7 billion in a transaction that was completed in July 2021. The former Slack CEO Stuart Butterfield, a key figure behind the EU complaint at the time, left Salesforce at the beginning of this year.

Updated at 6:40 a.m. with Microsoft statement.

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