The Age of Tech Unicorns

Stewart Butterfield had one objective when he set out to raise money for his startup last fall: a billion dollars or nothing. If he couldn’t reach a $1 billion valuation for Slack, his San Francisco business software company, he wouldn’t bother. Slack was hardly starving for cash. It was a rocket ship, with thousands of people signing up for its workplace collaboration tools each week. What Slack needed, Butterfield believed, was the cachet of the billion-dollar mark.