Enterprise software giant Salesforce has signed a definitive agreement to buy work communications platform Slack for US$27.7 billion, the largest acquisition ever made in Salesforce's history. The deal, first rumored in November and confirmed just days later on December 1, will add Slack's platform to Salesforce's existing software suite, which had previously lacked a collaboration tool, and according to the official announcement, Slack will be utilized as the “new interface for Salesforce Customer 360”.

Calling Slack “one of the most beloved platforms in enterprise software history”, Salesforce chair and CEO Marc Benioff said: “This is a match made in heaven. Together, Salesforce and Slack will shape the future of enterprise software and transform the way everyone works in the all-digital, work-from-anywhere world.”

Stewart Butterfield, Slack CEO and co-founder, said: “As software plays a more and more critical role in the performance of every organization, we share a vision of reduced complexity, increased power and flexibility, and ultimately a greater degree of alignment and organizational agility. Personally, I believe this is the most strategic combination in the history of software, and I can’t wait to get going.”

This deal is the latest move in Salesforce's diversification strategy, which has used acquisitions to enter assorted new markets in previous years. In 2019, for example, Salesforce had acquired data analytics and visualization company Tableau for US$15.7 billion; in 2018 it acquired API integration company MuleSoft. It also entered e-commerce and e-marketing through acquisitions in earlier years.

In addition, acquiring Slack also represents a way for Salesforce to compete more effectively with Microsoft, which integrates its popular Teams communication platform into the widely-used Office 365.