Slack has filed a complaint against Microsoft over Teams

Ever since Microsoft introduced Teams, an enterprise communication tool to rival Slack, the two companies have had something of a back-and-forth regarding the competition between the two services. Upon launching Teams, Microsoft said that "little companies come and go" while referring to Slack, while adding that Microsoft offered a wider range of business products. More recently, Slack CEO Stewart Butterfield said that Slack doesn't see Teams as a threat.

Despite that, however, Slack announced today that it has filed a complaint to the European Commission, accusing Microsoft of "illegal and anti-competitive" behavior with its approach to Teams. Specifically, the company calls out Microsoft for bundling Teams with its Microsoft 365 suite of products, forcing it to be installed on many machines with no way to remove it by itself, all while "hiding the true cost to enterprise customers".

Jonathan Prince, Vice President of Communications and Policy at Slack, said that the company's product threatens Microsoft's presence in the enterprise space as whole, since it helps replace traditional email, which Slack refers to as "the cornerstone of Office". He added:

“But this is much bigger than Slack versus Microsoft – this is a proxy for two very different philosophies for the future of digital ecosystems, gateways versus gatekeepers (...). Slack offers an open, flexible approach that compounds the threat to Microsoft because it is a gateway to innovative, best-in-class technology that competes with the rest of Microsoft’s stack and gives customers the freedom to build solutions that meet their needs. We want to be the 2% of your software budget that makes the other 98% more valuable; they want 100% of your budget every time.”

David Schellhase, General Counsel at Slack, stated that Slack simply wants competition to be fair and to have a level playing field, while accusing Microsoft of "reverting to past behavior".

With the complaint now filed to the European Commission, it's up to the agency to decide whether it needs to open a formal investigation on Microsoft's practices with Teams.