Quorum Cyber to acquire Ontinue in Microsoft security deal

Quorum Cyber has agreed to acquire Ontinue, combining two Microsoft-focused cyber security providers.

Financial terms were not disclosed. The companies will continue to operate independently until the transaction closes, subject to customary conditions and any required approvals.

The proposed acquisition would bring together Quorum Cyber's managed detection and response, incident response and professional services with Ontinue's managed extended detection and response offering and its Agentic Security Operations Centre. Both companies focus on Microsoft security products and are members of the Microsoft Intelligent Security Association.

Founded in Edinburgh, Quorum Cyber said the combined group aims to offer a broader cyber resilience service spanning secure AI adoption, security improvement, round-the-clock threat detection, incident response and recovery. The businesses also expect to expand their reach across North America, the UK and the DACH region.

Eterna Growth Partners, Quorum Cyber's current majority investor, will remain the majority investor in the combined company.

Microsoft focus

The transaction reflects a broader shift in the security market, as service providers seek to integrate AI tools more closely into day-to-day defence operations rather than use them for isolated tasks. Here, the companies are positioning the deal around Microsoft's own shift towards AI agents in security operations.

The combined organisation would support customers using Microsoft Sentinel, Microsoft Defender and other Microsoft security and collaboration tools. The planned portfolio would also deepen support for Microsoft Azure, Defender XDR, Entra, Purview, Microsoft 365 Copilot, Microsoft Security Copilot, Microsoft Scout and Agent 365.

The companies argue that security teams need systems that can handle a growing volume of alerts and decisions more quickly, while leaving strategic oversight and key decisions to human operators. That approach underpins Ontinue's Agentic SOC model, which uses AI agents within customer-defined controls.

Kevin Hanes, Chief Executive Officer at Quorum Cyber, said that view drove the transaction.

"AI has changed the speed, scale and economics of cyber defense. The future is not security teams managing more tools; it is experienced defenders directing AI-powered systems that can work continuously and act at machine speed, with humans firmly in control," said Kevin Hanes, Chief Executive Officer at Quorum Cyber.

"The union of Quorum Cyber and Ontinue is a major step forward in evolving our portfolio for that future and bringing to market the largest Microsoft-first MXDR combining machine intelligence with the judgment, expertise and accountability customers need to move forward with confidence," Hanes said.

Market pressure

The rationale for the deal centres on the growing use of AI by both attackers and defenders. Security providers are under pressure to show they can process signals faster, investigate incidents more efficiently and reduce analysts' workloads without removing accountability from human teams.

According to Moritz Mann, Chief Executive Officer at Ontinue, the company has built its offering around that idea from the outset. He said Ontinue was founded on the belief that AI should be built into security operations rather than added later.

"In the Autonomous Threat Era, when attackers operate at machine speed while most defenses still decide at human speed, Ontinue was founded on the conviction that AI must be intrinsic to security operations, not a bolt-on," said Moritz Mann, Chief Executive Officer at Ontinue.

"Our Agentic SOC platform overcomes the human-decision bottleneck by letting AI agents investigate, decide and act at machine speed within customer-defined guardrails, while people stay in control of risk and accountability. Quorum Cyber shares that belief and brings global scale, deep threat intelligence and a proven ability to turn Microsoft innovation into stronger security outcomes. Together, we will set the standard for how security operations are run in the AI era, giving customers broader protection, greater resilience and the confidence to adopt AI securely, while creating an exciting new chapter for our people," Mann said.

Partner landscape

The transaction also highlights the importance of Microsoft's partner ecosystem in cyber security services. Quorum Cyber said it holds all Microsoft Security specialisations and was named Microsoft Security MSSP of the Year for 2025. Ontinue described itself as a five-time Microsoft Gold Partner and a previous recipient of Microsoft partner awards.

That shared alignment gives the combined business a clear route into organisations standardising on Microsoft's security stack and related workplace software. It also suggests the merged company will focus on customers seeking external security operations support closely tied to existing Microsoft deployments, rather than a broader multi-vendor approach.

For Quorum Cyber, the acquisition expands both geography and product depth as demand rises for managed security services spanning prevention, monitoring, response and recovery. For Ontinue, it offers access to a larger platform and investor backing while preserving a strategy built around AI-led security operations.

Until the deal closes, the two companies will continue to operate independently, with Eterna Growth Partners retaining a controlling stake in the enlarged group.