A number of important merger and acquisition (M&A) announcements were made in October 2026, with the need to enhance AI security a recurring theme.
The biggest headline deal of the month was Proofpoint entering into a definitive agreement to buy AI security specialist Varonis for $6.3bn. Once the transaction has closed, it is expected to make Proofpoint one of the biggest world’s largest pure-play cybersecurity providers.
Another notable announcement came in the form of frontier AI firm Anthropic seeking to boost its security offerings by acquiring Opaque Systems.
Several of Anthropic’s agentic AI models have reportedly gone “rogue” this year, resulting in them hacking third-party systems. This activity has highlighted the need for stronger guardrails around such models.
CyberFOX Acquires Microsoft 365 Security Specialist Optimize365
On October 8, cybersecurity software provider CyberFOX announced it had acquired Optimize365, a Microsoft 365 tenant monitoring and hardening specialist.
The transaction aims to expand CyberFOX’s ability to help IT teams identify and address security risks across both endpoint and cloud environments, extending into the Microsoft 365 environment.
Optimize365 will continue to operate under the Optimize365 brand within the CyberFOX portfolio in the near term, and current customers will not experience any disruption to service, support or contracts. CyberFOX plans to integrate Optimize365 into its partner program and product roadmap over the coming quarters.
The deal follows CyberFOX’s acquisition of SASE provider Timus Networks in June 2026.
11:11 Completes Purchase of Select IBM VMware Cloud Service Provider (VCSP) Customers
11:11, a managed infrastructure solutions provider, announced it had completed the acquisition of select IBM VMware Cloud Service Provider (VCSP) enterprise customers.
The transaction follows efforts by Broadcom, which owns VMware, to optimize its VCSP partners program. 11:11 will use the acquisition to expand its ability to support complex enterprise migrations through an integrated portfolio of cloud infrastructure, connectivity, cyber resilience and recovery services across North America, EMEA, APAC and South America.
The acquisition of select IBM VCSP enterprise customers will mark 11:11’s eighth purchase of a VMware CSP business and eleventh acquisition overall.
Quantum Platform InoQ to Acquire Elisity for $1.3bn
Quantum computing platform IonQ revealed it reached a definitive agreement to acquire zero trust provider Elisity for an all-stock transaction of up to $1.3bn. Announced on October 12, the acquisition will see IonQ develop an expanded cybersecurity platform that identifies and protects against large language model (LLM) and emerging quantum threats.
The transaction is expected to close in the fourth quarter of 2026.
Anthropic to Acquire AI Security Startup Opaque Systems
AI frontier firm Anthropic has agreed to acquire AI security company Opaque Systems in a deal announced on October 13. Opaque’s technology enables organizations to run AI workloads on sensitive data with hardware-enforced protections.
The startup’s team will join Anthropic to help the tech provider enhance security controls across its AI models, and continue to develop new ways to improve how AI is built and secured.
The announcement came shortly before Anthropic filed Form S-1 with the SEC on October 26, relating to its proposed initial public offering.
Proofpoint Agrees $6.3bn Varonis Transaction
On October 15, Proofpoint announced it had entered into a definitive agreement to acquire Varonis for $6.3bn. The all-cash transaction will allow the development of a unified platform that helps organizations adopt AI securely, including access controls and preventing data loss.
The combined company is expected to serve millions of organizations globally, making it one of the world’s largest pure-play cybersecurity providers.
The transaction is expected to close in the first half of 2027. Proofpoint is a portfolio company of private equity giant Thoma Bravo.
Cohere to Acquire Vulnerability Remediation Specialist AISLE
Cohere announced a proposed agreement to acquire AISLE, a company building autonomous systems to discover and remediate previously unknown vulnerabilities in critical software, on October 15.
AI developer Cohere plans to use AISLE’s technology to build the world's leading sovereign AI platform, which helps organizations deploy AI models securely in their enterprise.
AISLE’s three founders will take leadership roles in Cohere spanning cybersecurity, corporate security, AI security research and frontier model development once the transaction closes.
Alchemy Technology Group Acquires Texas-Based Cybersecurity Firm
Texas cybersecurity advisory firm Alchemy Technology Group has acquired Freeit Data Solutions, an Austin-based provider of data management, infrastructure, and cybersecurity solutions.
The transaction, announced on October 28, will strengthen Alchemy's presence in Texas and strengthens its capabilities across security and compliance, hybrid cloud, backup and protection, storage and hyperconvergence, virtual desktop infrastructure, data archiving, and consulting services.
Alchemy is a portfolio company of private equity firm Advance Investment Management.