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Slack files competition complaint against Microsoft in the EU

Slack files competition complaint against Microsoft in the EU


Slack claims Microsoft is reverting to its past behavior

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Illustration by Alex Castro / The Verge

Slack says it has filed an anti-competitive complaint against Microsoft with the European Commission. “The complaint details Microsoft’s illegal and anti-competitive practice of abusing its market dominance to extinguish competition in breach of European Union competition law,” says Slack in a statement. Slack alleges that Microsoft has “illegally tied” its Microsoft Teams product to Office and is “force installing it for millions, blocking its removal, and hiding the true cost to enterprise customers.”

“Microsoft is reverting to past behavior,” claims David Schellhase, general counsel at Slack. “They created a weak, copycat product and tied it to their dominant Office product, force installing it and blocking its removal, a carbon copy of their illegal behavior during the ‘browser wars.’ Slack is asking the European Commission to take swift action to ensure Microsoft cannot continue to illegally leverage its power from one market to another by bundling or tying products.”

Slack has persistently claimed that Microsoft Teams is not a true competitor, largely because it’s more focused on video calls and meetings. That’s clearly not true, and Slack and Microsoft have been caught in a battle for the future of workplace communications for months now.

Microsoft Teams stock
Microsoft Teams

Microsoft claimed Slack doesn’t have the “breadth and depth” to reinvent work, and Slack CEO Stewart Butterfield has previously said that Microsoft is “unhealthily preoccupied with killing us.”

“We created Teams to combine the ability to collaborate with the ability to connect via video, because that’s what people want,” a Microsoft spokesperson tells The Verge. “With COVID-19, the market has embraced Teams in record numbers while Slack suffered from its absence of video-conferencing. We’re committed to offering customers not only the best of new innovation, but a wide variety of choice in how they purchase and use the product. We look forward to providing additional information to the European Commission and answering any questions they may have.”

The competition between the two companies first began nearly four years ago when Slack paid for a full-page newspaper ad to “welcome” Microsoft Teams as a competitor. Microsoft overtook Slack usage a year ago, and has hit big user numbers recently thanks to pandemic-related demand. Microsoft revealed it had 75 million daily active users of Microsoft Teams back in April, and the company may well update that figure during its earnings call later today.

Slack previously revealed it has 12 million daily active users back in October, but the company has not publicly updated this number ever since. Slack did break user records back in March as more businesses turned to remote working.

The European Commission will now assess Slack’s complaint to determine whether it meets grounds for a formal investigation. Microsoft hasn’t faced a formal antitrust investigation in Europe since 2008, when the company was eventually forced to offer a browser ballot choice after bundling Internet Explorer with Windows. Microsoft was later fined $730 million for failing to include the browser ballot screen in Windows 7 SP1.

Update July 22nd, 12:41PM ET: Added comment from Microsoft.