Slack CEO tweeted an attempt to explain the antitrust lawsuit against Microsoft.

More than a year ago, Microsoft Teams had 180 million users, according tomedia onMSFT. Asked about the milestone, Stewart Butterfield, Slack’s chief executive, said the platform posed no threat to the competing platform. A year later, Butterfield was using Twitter to defend Slack’s new antitrust lawsuit against Microsoft in the European Union, claiming the company was crushing competition.

Slack CEO tweeted an attempt to explain the antitrust lawsuit against Microsoft.

In a lengthy and sometimes inexplicable Twitter “storm,” Butterfield sought to clarify Slack’s new antitrust lawsuit against Microsoft and the company he believed was worse off.

According to a public statement about the lawsuit, Slack argued that Microsoft’s bundling of its enterprise chat features with its dominant productivity suite constituted the company’s anticompetitive behavior.

Slack CEO tweeted an attempt to explain the antitrust lawsuit against Microsoft.

The crux of Butterfield’s online rants seems to be that people who are already using Microsoft’s Office Productivity Suite don’t have a chance to try Slack and then opt for Slack instead of Teams. Butterfield and other Slack executives want the EU to force Microsoft to remove Slack from office as a stand-alone product and charge it “fair prices”.

While Slack’s argument sits in contrast to Microsoft’s previous antitrust lawsuit in 2000, it seems likely that the company is more of a nostalgia than a real case.

Slack is seeking to hold Microsoft “responsible” in the European Union, which can be said to be less restrictive at the consumer level than the U.S. anti-competitive behavior definition. The potential problem for Slack is that in the antitrust investigation against Microsoft in the 1990s, the company was not identified as “bundled” but as an other illegal means, and its corporate chat competition was less obvious.

In addition, Butterfield and Slack are targeting Microsoft’s crosshairs, but may be blindsided by a more immediate threat in Google’s latest bundling effort, which poses a greater risk to Slack’s long-term growth.