Upwind Secures $400 Million Series C at $3.8 Billion Valuation After Spurning Datadog Acquisition Attempt

The landscape of cloud infrastructure security continues to evolve at a blistering pace, marked by massive capital injections and fierce corporate maneuvering. Upwind, a San Francisco-headquartered startup specializing in artificial intelligence-driven cloud security, has successfully closed a $400 million Series C funding round. This latest financing event values the four-year-old enterprise at an impressive $3.8 billion. The funding round was spearheaded by Bessemer Venture Partners, with continued financial backing from existing institutional investors, including Greylock Partners and Craft Ventures.

This capital raise arrives merely nine months after Upwind secured a $250 million financing round in January 2026, which valued the company at $1.5 billion. The rapid succession of funding rounds highlights the explosive market demand for advanced cloud security solutions, as organizations globally grapple with increasingly sophisticated, AI-accelerated cyber threats.

Behind the Scenes of the Mega-Round and Datadog’s Bid

The path to closing Upwind’s $400 million Series C was fraught with high-stakes corporate drama. According to sources familiar with the matter, the funding round had been in development for months when it nearly collapsed due to an unexpected acquisition maneuver. Publicly traded observability giant Datadog stepped forward with an acquisition offer to buy Upwind outright.

Datadog, renowned for providing software monitoring and analytics tools, sought to integrate Upwind’s real-time runtime security capabilities into its expansive product ecosystem. However, Datadog’s acquisition proposal failed to provide a financial premium over the $3.8 billion valuation established by the venture capital investors leading the Series C round. Faced with an offer that did not surpass their independent market valuation, Upwind’s leadership and board of directors opted to reject the buyout bid, choosing instead to preserve the company’s independence and pursue its standalone growth trajectory.

By walking away from Datadog’s acquisition overtures, Upwind’s executive team signaled immense confidence in the company’s future valuation and market potential. Nevertheless, market analysts note that given the current sluggish market for technology initial public offerings, an eventual acquisition by a larger enterprise technology player remains a distinct and probable long-term outcome for the startup.

Exceptional Financial Growth and Revenue Metrics

Upwind’s astronomical valuation is underpinned by stellar financial performance. The startup has demonstrated hyper-growth, consistently adding between $20 million and $30 million in annualized recurring revenue (ARR) each quarter. Financial projections indicate that Upwind is on track to close the fiscal year with approximately $90 million in ARR.

This revenue trajectory puts the company’s valuation multiples into sharp focus. Both the venture capital consortium and Datadog evaluated Upwind at more than 40 times its forecasted ARR—a standard valuation metric used across the software-as-a-service (SaaS) and cybersecurity sectors. While a 40x ARR multiple signifies a premium valuation reserved for top-tier software performers, it remains conservative when compared to other market peers. For context, earlier this year, fast-growing cybersecurity rival Cyera commanded an 80x ARR multiple as it pursued a $12 billion valuation, underscoring the fierce investor appetite for specialized security assets.

The Genesis and Vision of Upwind

Upwind was founded by Amiram Shachar, a seasoned entrepreneur with a proven track record in cloud infrastructure management. Prior to launching Upwind, Shachar founded Spot.io (formerly Spotinst), a cloud spend management startup that successfully optimized cloud infrastructure costs for enterprises. In June 2020, Shachar orchestrated the sale of Spot.io to storage and data management giant NetApp for $450 million.

Drawing from his deep expertise in cloud architecture, Shachar established Upwind to fundamentally reshape how enterprises defend their cloud environments. Unlike traditional security tools that rely on static configurations or post-breach analysis, Upwind champions "runtime" security. This methodology focuses on active services, identifying vulnerabilities, detecting active threats, and executing remediation in real time. As modern cloud environments grow increasingly dynamic and complex, runtime security has emerged as a critical line of defense, enabling security teams to neutralize attacks before they can cause widespread enterprise damage.

The Broader Cybersecurity and AI Software Wave

Upwind’s rapid ascent is part of a much larger macroeconomic and technological shift. Artificial intelligence has fundamentally transformed the cybersecurity paradigm, creating new classes of automated threats while simultaneously driving the demand for AI-powered defense mechanisms.

According to Tomasz Tunguz, general partner at Theory Ventures and a prominent venture capital commentator, cybersecurity is positioned to become the third massive wave of enterprise AI software spending. Following the initial waves of enterprise investment in AI coding assistants and AI-driven customer support tools, corporations are now channeling substantial capital into intelligent security infrastructure capable of matching the speed and sophistication of AI-driven cyber attacks.

As organizations accelerate their migration to the cloud, the attack surface expands exponentially. Traditional, signature-based security tools are proving inadequate against automated, generative AI-powered exploits. This structural shift has created a lucrative market window for specialized startups like Upwind that can leverage AI to provide continuous, real-time visibility and automated threat mitigation.

Market Implications and Industry Outlook

The events surrounding Upwind’s latest funding round and rejected acquisition bid offer valuable insights into the current state of the enterprise technology and venture capital markets.

First, well-capitalized startups with exceptional unit economics and high revenue growth rates retain the leverage to remain independent, even when faced with multi-billion-dollar acquisition bids from established public technology companies. Upwind’s leadership evidently believes that the company’s addressable market and technological moat will yield a valuation significantly higher than $3.8 billion in the coming years.

Second, the intense acquisition interest from legacy players like Datadog demonstrates that incumbent technology giants are feeling pressure to incorporate advanced cloud-native security capabilities into their product suites. As observability and security continue to converge, software monitoring platforms are increasingly looking to acquire specialized security startups to maintain a competitive edge.

Finally, the cybersecurity sector remains one of the few bright spots in the broader tech M&A and financing landscape. Despite broader macroeconomic uncertainties and a cautious IPO market, venture capital firms continue to deploy massive amounts of dry powder into category-defining cybersecurity enterprises that demonstrate clear product-market fit and explosive top-line growth.

As Upwind absorbs its newly acquired capital, the company faces the challenge of scaling its operations, expanding its engineering and go-to-market teams, and maintaining its rapid ARR growth trajectory. Whether Upwind eventually chooses to test the public markets or entertain future strategic acquisition offers, its position as a heavyweight in the cloud security arena has been firmly cemented. Representatives for both Upwind and Datadog have been approached for formal comment regarding the acquisition discussions and the Series C financing.