Blackwall raises £75m at £1.6bn valuation as AI agents crowd the web

The Estonian-founded company, which filters traffic from inside hosting providers’ own infrastructure, has roughly quadrupled its valuation since March 2025 and will open operations in 12 regions.

Blackwall, a company that screens web traffic on behalf of hosting providers, has raised £75m in a Series C round that values it at £1.6bn. The round, announced on Tuesday, was led by AVP, with existing investors Dawn Capital, MMC Ventures and Tera Ventures also taking part. International coverage gave the figures in dollars: $100 million at a valuation of $2.2 billion.

The deal puts a price on a problem that artificial intelligence has made larger. A growing share of requests to websites now comes from software rather than people, including AI agents acting for users, and hosting companies pay to serve all of it. Blackwall says its system already sits in front of millions of websites and filters billions of requests a day, separating real visitors and legitimate automated traffic from malicious bots and abuse.

Its commercial model sets it apart from larger rivals. Hyperscale clouds and content-delivery networks sell security directly to website owners, often competing with the hosts that serve those same customers. Blackwall instead installs its software inside the hosting provider’s infrastructure, covering bot mitigation, protection against distributed denial-of-service attacks, a web application firewall, load balancing, server-side encryption and the management of agentic AI traffic. Providers can then bundle and sell these features under their own names. The company argues this cuts their server costs, because unwanted traffic is stopped before it arrives, while creating new revenue they did not have to build themselves.

Blackwall was founded in 2019 by Nikita Rozenberg, its chief executive, and Denis Prochko, its chief technology officer, under the name BotGuard. According to Dawn Capital, the idea came from experience: a vegetarian recipe site Prochko had launched as a side project drew heavy bot traffic, some of it aimed at stealing content, committing ad fraud or probing for weaknesses. The company is headquartered in Tallinn. In March 2025 it closed a €45 million Series B and renamed itself Blackwall, in a round led by Dawn.

The new valuation had been anticipated in Estonia. Last month TopTech, an annual ranking of the country’s 30 most valuable technology companies, estimated Blackwall’s worth had risen from around €221 million to €1.03 billion in a year, placing it fifth behind Wise, Bolt and Veriff. Rando Rannus of Siena Secondary Fund, a co-author of the ranking, attributed the figure to strong revenue growth and high valuations across its cybersecurity peers, and predicted a funding round would confirm it. Roi Carthy, Blackwall’s executive chairman, told TechCrunch the round had increased the company’s valuation fourfold since its last raise in 2025.

Rozenberg described the opportunity in structural terms. “The web is becoming more automated, more distributed and more complex, but the infrastructure that powers it remains highly fragmented,” he said. Hosting, which the company sizes at $200bn a year, remains split among many regional providers because infrastructure needs to sit close to the businesses it serves.

Investors framed the bet around agent traffic. Warda Shaheen, a general partner at AVP, said the company was “already the layer in front of millions of websites,” and that whoever occupies that position becomes indispensable as more traffic comes from agents. Norman Fiore of Dawn Capital, which led the previous round, warned that “a tsunami of agents will overwhelm infrastructure optimised for human traffic.”

Some of the company’s framing is disputed. Blackwall has described the valuation as making it Europe’s most valuable cybersecurity scaleup, a title Tech Funding News noted is contested, since Exein made the same claim at a $1.7 billion valuation. Blackwall has not published revenue or profitability figures, and the TopTech estimate was derived from revenue projections rather than audited accounts.

The money will fund expansion into 12 regions across North America, Europe, Asia-Pacific and the Middle East, along with new traffic security tools intended to let providers handle a larger share of their customers’ needs through a single layer. Dawn’s Fiore said at the time of the Series B that Blackwall had only scratched the surface of the US and APAC opportunity. This round is its first test of how much of that ground it can take.