Slack has filed a formal antitrust complaint against Microsoft in Europe over the way it bundles Microsoft Teams with its Office 365 suite.  

The communications platform is accusing Microsoft of “illegally” bundling the Teams app into its market-dominant productivity suite and hampering competition by making it unremovable. 

In its complaint, Slack said it was confident on the “merits” of its own product, but it couldn’t ignore the “illegal behaviour” that deprives customers of access to the tools and services they want. It accuses Microsoft of “force installing” Teams for millions of users and hiding the true cost to enterprise customers.

Slack says it simply wants fair competition and is asking the European Commission (EC) to be a neutral referee in what is the legal culmination of a years-long spat between the two companies. 

“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,” said Jonathan Prince, VP of communications and policy at Slack.

“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.”

The war between Slack and Microsoft has intensified during the coronavirus pandemic, with remote working surging. Microsoft announced it had surpassed 44 million users at the start of the UK and US lockdown, but Slack disputed the figures citing its 365 bundles.  

“Microsoft is reverting to past behaviour. 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 behaviour during the ‘browser wars’,” said David Schellhase, Slack’s general counsel. 

“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.”

CloudPro has approached Microsoft for comment.