https://www.theverge.com/2018/7/26/17619482/slack-hipchat-acquisition-stride-atlassian-partnership-microsoft-teams-competition

Slack made a surprise announcement today that it’s acquired Hipchat, once a primary competitor to its workplace chat service, from enterprise software giant Atlassian. As part of the partnership between Slack and Atlassian, Hipchat will be shutting down and the two companies will work together to migrate all of its users over to Slack. The same goes for Stride, the chat and collaboration successor to Hipchat that Atlassian launched last year.

Atlassian clarified that Slack is only buying the intellectual property behind the two products, and that the two companies will be working on future integrations together.