Butterfield created the photo-sharing website Flickr, but these days most of his wealth is tied to Slack, an inter-office communications platform, which he feels can replace—or at least reduce—internal email.
And he may be right. Slack is no longer a scrappy upstart; it has more than six million active daily users, two million of whom pay for the privilege. Those numbers are each up from early 2014, when the company got started. What’s behind the growth? Slack has a devoted following, and not just among bleeding-edge technophiles: EBay, Sony, Nordstrom, PayPal and—ahem—Canadian Business have all become Slack offices. Recent partnerships have helped too. Last July, Slack and its venture capital partners awarded 11 software startups money to build tech that complements its core offering, as part of its US$80-million Slack Fund; the following September, Slack entered into what it calls a “deep product partnership” with Salesforce that is hoped to help users of both platforms share information more easily.
Of course, with great early success comes great expectations—and great competition. Facebook has announced plans to develop Workplace, a Slack competitor; Microsoft quickly followed with Teams, the aforementioned launch that spurred a full-page ad. But Slack and its investors don’t seem too troubled. In July, Butterfield and his team raised US$250 million following an earlier round of US$360 million that they reportedly have yet to dip into, pegging Slack’s valuation at US$5 billion.
Updated Thursday, November 9, 2017
#46: Guy Laliberté
#47: Stewart Butterfield
#48: Terry Matthews ▼