Upwind, a San Francisco-based cloud infrastructure security startup, raised $400 million in Series C funding at a $3.8 billion valuation led by Bessemer Venture Partners, with participation from Greylock Partners and Craft Ventures.
The round comes nine months after Upwind closed a $250 million Series B at a $1.5 billion valuation. Datadog, a publicly traded observability software company, attempted to acquire Upwind but did not offer a premium above the $3.8 billion valuation set by venture investors, so Upwind chose to remain independent.
Upwind projects ending the year at roughly $90 million in annualized recurring revenue, having added $20 million to $30 million each quarter. The valuation represents more than 40 times forecast ARR.
Founder Amiram Shachar previously sold Spot.io, a cloud spend management startup, to NetApp for $450 million. Upwind describes its security approach as "runtime" security, alerting and remediating attacks in active services in real time.
Upwind continues to draw acquisition interest from other companies, according to a person familiar with the startup.