Cloud data platform unicorn Snowflake started trading on the New York Stock Exchange today under the ticker symbol “SNOW” in what is expected to be the largest-ever initial public offering (IPO) for a software company.

The 8-year-old startup plans to sell 28 million shares at $120 each, which means Snowflake’s  IPO will raise at least $3.36 billion pushing its value to $33.3 billion. Investors Salesforce.com and Warren Buffett's Berkshire Hathaway agreed to concurrently purchase $250 million in shares at the IPO price. However, Snowflake will likely raise more than $4 billion because its underwriters can buy an additional 4.2 million shares over the next 30 days.

The company had already raised its IPO price from $85 to $110 before settling on $120 per share.

Snowflake provides data warehouse services using a cloud-based architecture offered through an as-a-service model. This allows enterprise customers to analyze data stored in a central repository using business intelligence tools or other analytics applications. Its platform supports the three largest public clouds — Amazon Web Services (AWS), Microsoft Azure, and Google Cloud — however, it also competes against these platforms.

According to its most recent filing with the U.S. Securities and Exchange Commission, Snowflake has 3,117 customers as of July 31 compared to 1,547 a year earlier. These customers include seven of the Fortune 10 and 146 of the Fortune 500. Snowflake more than doubled its revenue over the last year, bringing in $96.7 million in fiscal 2019 and growing to $264.7 million in fiscal 2020.

“Snowflake took the cloud playbook, rewrote it and won,” said Clumio CEO Poojan Kumar. Clumio provides cloud-based enterprise backup services, and Kumar is a self-described “strong admirer” of Snowflake.

“Snowflake disrupted the crowded, well-established data warehousing market by rapidly innovating a seamless service that tapped the scale, elasticity and economics of the public cloud,” Kumar said in an emailed statement. “Snowflake transformed the old-school data warehouse into a cloud data platform and completely changed the way companies do business today — and its customers have felt the biggest benefit with huge cost savings and productivity increases with faster access to their data.”