Atlassian's shares soar in market debut

Shares of Australian business software maker Atlassian soared as much as 33.3 percent in their market debut today, valuing the company at about US$5.85 billion (A$8 billion) in one of the most highly valued initial public offerings of the year.

Atlassian's strong debut signals to investors that among the crop of 145 tech unicorns - venture-backed private companies worth US$1 billion or more - there are still some that are not overvalued.

The company's IPO raised US$462 million after the shares were priced at US$21 each, above the expected range of US$19-$20.

The stock hit a high of US$28.05 in early trading.

Sydney-based Atlassian, which makes collaboration and management software, was valued at US$3.3 billion in its last private valuation.

The company has about 51,000 customers in more than 160 countries, including NASA, Tesla Motors and the US Department of Treasury.

Atlassian joins online dating company Match Group and mobile payments firm Square, which also popped on their first day of trading despite overall negative sentiment for Silicon Valley startups and a broadly weak IPO market.

Several tech IPOs have performed poorly over the past year, and mutual fund investors including Fidelity Investments have been marking down the value of their private tech holdings.

Improving IPO market sentiment is especially critical now that calls are growing for unicorns lingering in the frothy private market to go public.

Goldman Sachs and Morgan Stanley are the lead underwriters for the offering