Initial public offerings may not have had their strongest year in 2015, but tech companies--many minted by Silicon Valley--really outran the pack.

More than any other sector, such companies have been associated with the "unicorn" phenomenon of private companies lavishly valued at $1 billion or more.

In many cases, consumers really got behind young businesses that captured their imaginations, with innovative technologies that dramatically re-envision how people approach the world. And tech businesses that went public ran the gamut, including mobile payments, online crafts marketplaces, and cloud-based storage.

True, this year also saw the air coming out of sky-high valuations, as is best epitomized by cloud storage company Box and payments technology provider Square, both of which saw their values bid down, by as much as 50 percent, in the days leading up to their IPOs.

Still, in a slack year that ranked with 2009 for the number and dollar value of IPOS, tech IPOs raked in nearly $4 billion, according to IPO researcher Renaissance Capital, compared with about $30 billion for all sectors.

Here are 10 of the biggest tech IPOs for 2015.

10. Rapid7

The big data threat analysis company looks at information flowing across the range of networks companies use today, looking for security and compliance issues. Based in Boston, the company raised $100 million in July through its IPO. The company's shares increased 50 percent in the first days of trading from an opening price of $16. Since then, investors have taken a more sober view. Shares are now trading about 2.5 percent below the stock's starting price.

9. Shopify

The online shopping software services business started by Tobias Lütke and Daniel Weinand, who are Inc. 35 Under 35 entrepreneurs, raised $131 million in May through its IPO. Its share price has risen steadily since then, notching a 58 percent gain from its opening price of $17.

8. Box

The cloud storage company, founded by Inc.'s 2013 Entrepreneur of the Year Aaron Levie, raised $175 million in a January offering. Like Square, it's one of the unicorns whose value was rapidly tamped down by the public market. Investors bid down Box's value from to $1.7 billion from $2.4 billion. Its stock price is about flat with where it started out, slightly below its initial $14 initial price.

7. Square

The payment-processing company founded by Jack Dorsey, also a co-founder of Twitter, became a poster child for unicorns whose price tags have been written down in recent months. But the company's underwriters blinked: By the time Square went public in November, the company saw its valuation drop to $3 billion from a lofty $7 billion, with shares priced at a very low $9. Perhaps that was prudent as shares are now trading up about 30 percent higher than the opening asking price. Square raised $243 million in its November public market bid.

6. Etsy

The online craft marketplace raised $266 million in April, but it has also seen its share price decline significantly, like many highly valued companies that went public this year. Shares originally priced at $16 have been on a steady downward march, following a dramatic pop in the weeks following its debut, which pushed shares close to $36. They are now are worth about $9.30.

5. Match Group

Known for its online dating sites and Tinder, the company raised $400 million in November. Shares popped about 30 percent from an opening price of $12, and are now trading at just over $13.

4. Pure Storage

The flash storage company raised $425 million in an October offering, where shares immediately dropped 6 percent from their opening price of $17. Its stock price has since recovered, after its first earnings report showed revenues nearly tripling in the third quarter compared with a year earlier, to $131 million.

3. Go Daddy

The frequently controversial serial entrepreneur Bob Parsons raised $460 million in a late March offering, after the domain hosting company spent more than 20 years as a private concern. And investors liked what they saw, bidding up the company's shares more than 30 percent on their first day, to $26. Today, shares are valued at more than $32 apiece.

2. Atlassian

Based in Sydney, Australia, the cloud provider of workplace-collaboration software ended 2015 with one of the biggest IPOs of the year. In December, it hauled in $462 million, after setting its shares at the high end of its price range, at $21. And the market liked the company's message of low-cost, Web-accessible software, bidding up the value of Atlassian shares by 33 percent on its first day.

1. Fitbit

There's been so much expectation around wearable technology, it makes sense that Fitbit raised a staggering $731 million for its June IPO. Yet Fitbit faces a crowded market, with Huawei's TalkBand and the Apple watch as two prime competing products. Still, Fitbit's health-data-tracking wristband comes with a price tag that's much lower than its top competitor, and it has something of a first-mover advantage that's likely to keep its share price floating at its current level of around $32.

Corrections and Amplifications: The original version of this story incorrectly ranked Go Daddy’s IPO. Its correct ranking on this list is number 3.


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