Slack, the $7 billion office messaging app that millennials love, just filed to go public in a really weird way

Beck Diefenbach/Reuters

Slack CEO Stewart Butterfield.

• Slack, the buzzy workplace chat platform, filed the paperwork on Friday to list its shares.
• The company has tapped into an interesting new trend for tech firms going public, doing a "direct listing" which avoids the usual Wall Street IPO process.
• It's one of the most hotly anticipated offerings in a year of blockbuster tech IPOs that include Uber, Lyft, Pinterest, and Zoom.
• Slack was reportedly valued at as much as $17 billion during secondary market trades, according to CNBC. Its official valuation stands at $7.1 billion after an August funding round.
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Slack, the workplace chat platform that's taken offices by storm, filed the paperwork to go public on Friday, kicking off the final countdown to its listing and shedding light on the financial happenings at one of Silicon Valley's most valuable startups.

Slack was last valued around $17 billion on secondary market trades, according to CNBC. It was officially valued at $7.1 billion after its latest financing round last August.

Slack plans to list on the New York Stock Exchange under the ticker symbol "SK" through a direct listing - a unique alternative to the IPO in which private shareholders such as investors and employees sell their holdings directly to the public.

Unlike a standard IPO, Slack won't raise a bunch of new cash from investors rushing to buy its stock, and it won't set a share price.

It's the second big tech company to go public in this way recently after Spotify did a direct listing in April.

Slack is trimming its losses but says it may never be profitable

The firm also lifted the lid on its financial performance over the last three years, reporting in 2017 a net loss of $146 million on $105.2 million in revenue, in 2018 a net loss of $140 million in $220.5 million in revenue; and in 2019 a $138.9 million loss on $400.6 million in revenue.

The firm wrote: "We expect to continue to incur net losses for the foreseeable future and we may not achieve or maintain profitability in the future.

"Because the market for Slack, and the features, integrations, and capabilities we offer on Slack, is rapidly evolving and has not yet reached widespread adoption, it is difficult for us to predict our future results of operations or the limits of our market opportunity."

The company expects a significant increase in operating expenses thanks to hiring and development.

It's a banner year for tech IPOs

Slack is the latest in the parade of unicorn tech companies, named such for their $1 billion-plus valuations, to go public this year.

Uber filed an amended S-1 early Friday with a price range of $44 to $50 per share. The company is expected to start trading in mid-May.

Ride-hailing company Lyft went public at the end of March in an IPO that valued the company at $21 billion. It was followed by the IT management company PagerDuty, which was valued at $1.76 billion. Last week brought two IPOs: video conferencing company Zoom, with a $9 billion valuation, as well online scrapbooking platform Pinterest, which was valued at $10 billion.