Salesforce to buy Slack in $27.7bn deal aimed at competing with Microsoft

Marc Benioff's company gains leverage against Microsoft's threat with the largest acquisition in its 21-year history

Business software pioneer Salesforce.com is buying work-chatting service Slack for $27.7bn in a deal aimed at giving the two companies a better shot at competing against longtime industry powerhouse Microsoft.

The acquisition announced Tuesday is by far the largest in the 21-year history of Salesforce. The San Francisco company was one of the first to begin selling software as a subscription service that could be used on any internet-connected device instead of the more cumbersome process of installing the programs on individual computers.