Cloud and AI security startup Upwind has closed a $400 million Series C round at a $3.8 billion valuation, led by Bessemer Venture Partners, after choosing to walk away from an acquisition offer from Datadog.
The round and the near-acquisition
The financing, negotiated over several months, nearly collapsed when Datadog, known for its software observability solutions, sought to acquire the company; according to a source familiar with the situation, Datadog did not offer a premium above the $3.8 billion valuation set by venture investors, leading Upwind to choose to remain independent.
The round comes nine months after Upwind closed a $250 million financing at a $1.5 billion valuation. Existing investors include Greylock Partners, Cyberstarts, Craft Ventures, Salesforce Ventures, Alta Park and TCV, with Canapi Ventures joining as a new investor.
Company numbers and founder track record
Upwind said the investment brings its total funding to over $800 million, which it is deploying to help defenders protect against what it calls the exponential risk that comes with AI's benefits, and makes it one of the most capitalized companies focused on cloud and AI security.
Founder Amiram Shachar previously sold his first company, Spot.io, to NetApp for $450 million in 2020. Upwind has over $50 million in recurring revenue, putting the $3.8 billion valuation at nearly 76 times that run rate, and revenue quadrupled in 2026.
The company has roots in Israel. The financing marks a sharp rise from the $1.5 billion valuation the company reached in January, reflecting investor appetite for cybersecurity companies securing cloud infrastructure and AI systems; Upwind had announced the $3.8 billion valuation in September and has now expanded the round to $400 million at that level.
Market context
The round illustrates broader momentum in cloud and AI security investing, where valuations have been climbing as enterprises move more workloads to cloud and adopt AI tooling that expands attack surfaces. Upwind positions itself as unifying cloud security with AI security in a single platform, and the $400 million war chest is aimed squarely at competing with larger observability and security vendors, including the one that tried to buy it. The jump from $1.5 billion in January to $3.8 billion in September, then the rapid closure of a $400 million extension at that valuation, tracks the wider repricing of AI-infrastructure security as enterprises treat AI workload protection as a budget line of its own.
For B2B buyers evaluating cloud security vendors, the independence decision is a signal about the company's roadmap: Upwind's stated plan is product expansion rather than absorption, with the new capital earmarked for scaling its platform. Whether that bet pays off will depend on how well the company converts its funding advantage into market share against entrenched incumbents.
There is also a valuation signal in the deal itself. Nine months ago Upwind raised $250 million at a $1.5 billion valuation; today it closed $400 million at $3.8 billion. Growth at that pace explains why a no-premium acquisition offer was so easy to refuse: a company compounding revenue fourfold while the market reprices AI security is worth more to its own shareholders than to an acquirer at a flat valuation. For security buyers, the practical implication is that the vendor landscape is consolidating around well-capitalized independents, and feature roadmaps will be funded accordingly.
For the competitive landscape, the deal redraws the cloud-security map. Datadog's failed approach means the observability giant now has to build or buy elsewhere if it wants Upwind's AI-security capabilities, while Upwind emerges with a war chest that can fund aggressive product expansion and go-to-market hiring. The company's public positioning is that cloud security and AI security are converging into a single platform problem, and the $400 million is explicitly allocated to building that platform rather than to servicing a merger. Incumbent vendors in cloud security will be watching whether Upwind converts funding into enterprise deals at the pace its growth rate implies.
For buyers, the practical checklist is short. Ask whether a vendor's roadmap is funded for product expansion rather than absorption, whether its security platform genuinely spans cloud and AI workloads, and whether the balance sheet behind the roadmap can survive a funding winter. Upwind now has unambiguous answers to all three, and the $400 million makes its independence decision costly for any future suitor to reverse. The broader lesson is that well-capitalized security independents are becoming harder to acquire cheaply, which changes the calculus for enterprises that had hoped consolidation would simplify their vendor shortlists. Incumbents in cloud security now face a two-front war: enterprises are consolidating security tooling, and the highest-growth startups are arriving with fresh capital and product roadmaps aimed at the same budgets. The outcome will be decided in procurement cycles, where platform breadth, ease of deployment, and price per protected workload matter more than marketing spend.
