Slacks unusual direct listing pegged at $26 per share by NYSE for a possible $15.7 billion valuation

The New York Stock Exchange has set a reference price of $26 for Slack in its upcoming direct listing.

Slack is expected to start trading Thursday on the NYSE under the ticker “WORK.”

Slack has relied on internal data based on secondary markets to gauge its valuation, a person familiar told Business Insider. The average trade was valued at $26.82.

The New York Stock Exchange has set a reference price of $26 per share for Slack, as the company prepares to start trading publicly in a direct listing expected tomorrow.

Since it's going public through a direct listing, the reference price is not an official price for the shares.

In a traditional IPO, the company's underwriters sell the public offering to investors at a set price. In this case, the reference price will be used by the designated market marker, Citadel Securities, to decide when the timing is right to start trading shares.

Slack and its team referenced internal data gathered from secondary markets to get an idea of an appropriate valuation, according to one person familiar with the conversations.

The volume weighted price was $26.82 as of May, the company said in a filing, though the high and low ranges between trades was broad, the person said.

Slack is expected to start trading Thursday on the New York Stock Exchange under the ticker symbol “WORK.”