Microsoft Teams will reportedly sit at center of EU antitrust probe based on Slack complaint
Slack accused Microsoft of using Office to gain Teams users. Now Microsoft will face an antitrust probe over the situation.
What you need to know
- The European Union will reportedly open an antitrust probe into Microsoft surrounding the tech giant's communication platform Microsoft Teams.
- The investigation is based on a complaint made by Microsoft competitor Slack in 2020.
- The core argument Slack made was that Microsoft has used its dominant Office suite of applications to get an unfair advantage for Teams.
Microsoft will face an antitrust probe by the European Union, according to a report by POLITICO. The investigation will focus on a complaint made by Slack in 2020 that alleges Microsoft used its dominant Office suite of applications to gain an advantage for Microsoft Teams. POLITICO cited four people familiar with the situation in its report.
Slack and Microsoft have had a rocky relationship over the past few years. The rivalry ramped up during the global pandemic that saw Teams gain a substantial market share in the communication space. In April 2020, Slack CEO Stewart Butterfield said that Teams was not a competitor to Slack (via CNBC). Oddly, an SEC filing made by Slack during the same period claimed the exact opposite (via The Verge).
Would Slack have even existed if it was not for the free access they had on top of, say, the Windows platform?
Microsoft CEO Satya Nadella
Microsoft CEO Satya Nadella clapped back against Slack and asked, "would Slack have even existed if it was not for the free access they had on top of, say, the Windows platform?"
Now, around two years after Slack's complaint, the European Union will reportedly open an antitrust probe into the situation. POLITICO reports that the European Commission will "escalate the probe quickly" and prepare a statement of objections.
Microsoft's rivals and customers have been sent requests for more information, according to the report.
The "assessment of the complaint is ongoing," said a European Commission spokesperson to POLITICO. Microsoft has not responded with a comment at the time of publication.
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Sean Endicott is a news writer and apps editor for Windows Central with 11+ years of experience. A Nottingham Trent journalism graduate, Sean has covered the industry’s arc from the Lumia era to the launch of Windows 11 and generative AI. Having started at Thrifter, he uses his expertise in price tracking to help readers find genuine hardware value.
Beyond tech news, Sean is a UK sports media pioneer. In 2017, he became one of the first to stream via smartphone and is an expert in AP Capture systems. A tech-forward coach, he was named 2024 BAFA Youth Coach of the Year. He is focused on using technology—from AI to Clipchamp—to gain a practical edge.
