Upwind, a startup that uses AI to find security risks and investigate attacks in cloud systems, has raised $400 million in a Series C funding round.
Bessemer Venture Partners led the round, with participation from Greylock Partners, Cyberstarts, Craft, Salesforce Ventures, Alta Park, Picture Capital, Swish Ventures, Cerca Partners, TCV, Penny Jar and Leaders Fund, Upwind said Wednesday. Canapi Ventures joined as a new investor.
The startup did not disclose its valuation in the announcement, but several news outlets reported that it reached $3.8 billion. Upwind was reportedly valued at $1.5 billion when it raised its $250 million Series B in January.
The Series C brings Upwind's total funding to more than $800 million. Earlier funding included a $100 million Series A in December 2024 and $80 million raised during its first year, which it announced in September 2023.
Founded in 2022, Upwind is led by co-founder and CEO Amiram Shachar, who previously co-founded cloud computing cost-management business Spot.io. Upwind's founding team also came from Spot, which NetApp acquired in 2020 reportedly for $450 million. Shachar later served as vice president and general manager of Spot by NetApp. Last year, NetApp sold Spot to Flexera for $100 million.
Upwind said it will use the funding to improve its products and develop new features. It also plans to add more security tools for identity, data, and AI.
What does Upwind do?
Upwind says it monitors cloud apps to help customers detect attacks and fix security weaknesses before hackers can exploit them.
"Upwind gave us visibility into what is actually running, not just what a scan found. That changed which risks we spend our time on," said Michael Cannizzo, chief information security officer at HedgeServ, in the announcement.
Upwind has three AI agents for different security tasks. Blue Agent examines data to detect, investigate, and respond to attacks; Red Agent tests whether hackers could exploit security weaknesses; and Green Agent finds changes that could resolve security issues across a customer's systems.
The startup has also launched an AI research lab for cybersecurity, aiming to secure AI systems using AI agents and testing and developing AI models and systems.
Upwind's annual recurring revenue has quadrupled since the start of 2026, Globes reported, estimating that it would reach at least $80 million this year. Bloomberg separately reported that Upwind is on track to reach nearly $100 million in annual recurring revenue by year-end, citing Shachar.
The funding follows conflicting reports about acquisition interest from Datadog, which sells software monitoring and security tools. The Information reported last week that Datadog had offered close to $4 billion for Upwind. CTech subsequently reported that the offer had not been made.