Slack's anticipated IPO is still expected to be an unusual 'direct listing,' and it could be a Silicon Valley game-changer

Jin S. Lee

Slack cofounder CTO Cal Henderson speaks at Business Insider's IGNITION conference in December, 2018.

• Slack confirmed on Monday that it's planning to go public soon.
• This will be one of the most anticipated IPOs of 2019 not just for its size but because of its method.
• Slack is planning on doing its IPO in an unusual way, a source says: a direct listing.

On Monday, Slack confirmed what had been rumored for weeks: it's planning on holding an IPO soon. The company took the unusual step of announcing, via press release, that it had filed confidential S-1 paperwork with the SEC.

Normally, a company keeps its confidential S-1 filing under wraps until 15 days before its roadshow, when companies are required to make it public. The confidential S-1, which includes a rundown of its financial performance and its plans for growth, allows a company to work with the SEC without public scrutiny.

In Slack's case, this press release is the strongest indication that the other rumors are also true: that Slack is going to go public via a direct listing and skip the traditional banker-led IPO.

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About two weeks ago, when IPOs were stalled during the partial government shutdown, Bloomberg's Matt Levine first reported on Slack's plans to do a direct listing.

And the direct listing is likely still the plan, a source familiar with Slack's thinking told Business Insider, even though Slack is working with a cadre of bankers on the IPO, including Goldman Sachs, Morgan Stanley and Allen & Co., as Bloomberg's Olivia Zaleski reports.

A direct listing doesn't have bankers as intermediaries buying and selling an initial batch of shares, so the company doesn't pay the banks big commission fees for that service.

Slack can instead sell directly to public investors right away. It may not even need to impose a lock-up period - meaning the company's current investors and owners can sell their shares right away, too.

Slack has a ton of investors, ranging from classic Silicon Valley VCs like Andreessen Horowitz, to mega-investor SoftBank Vision Fund. It's raised $1.22 billion as a private company, and along the way took on institutional investors as investors, too, such as T. Rowe Price. That means that Slack doesn't need a banker to provide introductions for its road show presentation - the world of finance is already very familiar with it.

With its last round of private financing, it earned a $7 billion valuation by selling shares at just under $12. That's won't be a hard share price to best on its first day of public trading, either, even with a direct listing, where share prices can be more volatile.

Should Slack use the direct listing method, other Silicon Valley unicorns with big name recognition and healthy balance sheets will almost certainly take notice, too. Spotify pioneered the idea of a large, tech direct listing IPO last year. Should Slack have success, no doubt others will follow.