Co-founder Stewart Butterfield of Slack, whose funding lifted the valuation of the software startup to more than $7 billion, is seen at the VivaTech trade fair in May 2018 in Paris Slack, the workplace collaboration software startup that aims to fuel a move away from email, said Tuesday it raised $427 million to give it a valuation of some $7.1 billion.
The latest capital round makes Slack one of the most richly valued "unicorns," or startups with private funding worth at least $1 billion.
Slack, which offers real-time messaging for the workplace, said in its announcement it has more than eight million daily active users and more than 70,000 "paid teams" that subscribe to its premium services.
"The way people work is changing, and we are committed to delivering the best product and experience for our customers in this new era," a Slack statement said.
"Our mission is to make people's working lives simpler, more pleasant, and more productive, and we are grateful for the support along the way."
Slack, created in 2013, has been a leader in the new segment but faces competition from the likes of Microsoft, Facebook and others offering workplace collaboration tools.
Analysts say Slack has found a niche, especially among small- and medium-sized businesses, where employees can face information overload from email.
The latest funding is led by Dragoneer Investment Group and General Atlantic, joined by funds and accounts advised by T. Rowe Price Associates, Inc. and Wellington Management, with Baillie Gifford and Sands Capital and existing investors, Slack said.
It previously raised some $841 million.
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