Slack says Microsoft's behavior is "a carbon copy of their illegal behavior during the 'browser wars.'"
London CNN Business  — 

Slack is ratcheting up its battle with Microsoft, filing an antitrust complaint in the European Union against its rival.

The company claims Microsoft (MSFT) is engaging in “illegal and anti-competitive practice of abusing its market dominance to extinguish competition” by tying in its own communications platform, called Teams, to its popular Microsoft (MSFT) Office suite. Slack (WORK) says in its complaint Microsoft (MSFT) force-installs Teams for millions of people and blocks its removal.

“We’re confident that we will win on the merits of our product, but we can’t ignore illegal behavior that deprives customers of access to the tools and solutions they want,” Jonathan Prince, Slacks’ Vice President of Communications and Policy said in a statement. “Slack threatens Microsoft’s hold on business email, the cornerstone of Office, which means Slack threatens Microsoft’s lock on enterprise software.”