Proofpoint has agreed to acquire data and AI security firm Varonis in an all-cash deal valued at roughly $6.3 billion, the two companies announced Thursday. It is the largest cybersecurity acquisition announced so far in 2026.
Under the terms of the deal, Varonis shareholders will receive $49.75 per share, a 52% premium over the company’s closing stock price on June 22, 2026, the last full trading day before sale rumors began circulating. The transaction is expected to close in the first half of 2027, with the two companies operating independently until then.
Thoma Bravo, the private equity firm that owns Proofpoint, is providing committed equity financing and has secured debt financing to fund the purchase. Ontario Teachers’ Pension Plan is also investing in Proofpoint as part of the deal.
Building a data and AI security giant
Proofpoint, founded in 2002 and based in California, has traditionally focused on email security and identity threat defense. Varonis, founded in 2005 and headquartered in Miami, specializes in data visibility and security, mapping sensitive data across cloud, SaaS and on-premises systems and tracking who can access it.
Varonis also brings its Atlas platform, which covers AI systems an organization builds or uses, offering AI inventory, posture management, security testing, runtime guardrails and compliance reporting, along with an email and browser security product and a managed data detection and response service.
The companies said the combined entity will serve more than 16,000 enterprises and millions of organizations worldwide, positioning it as one of the largest pure-play cybersecurity companies and, according to Proofpoint, the industry’s largest data and AI security organization. The stated goal is a platform that helps organizations adopt AI confidently by finding and protecting sensitive data and controlling what people and AI systems can access.
Both companies have been active on the AI security front recently. Proofpoint acquired AI security and governance company Acuvity in February, around the same time Varonis acquired AI trust, risk, and security management provider AllTrue.ai for $150 million. Both firms are also known for cybersecurity research; Varonis researchers recently demonstrated manipulating Microsoft’s Copilot Personal into explaining how to hack itself, while Proofpoint analysts published research this month on a high-level, apparently China-backed espionage phishing campaign.
Part of a busy M&A year
The deal adds to a wave of major cybersecurity consolidation in 2026, including Accenture’s plan to acquire a majority stake in Dragos as part of a broader $4.175 billion transaction, and Cyera’s $1 billion acquisition of Oasis Security, which closed in September. SecurityWeek has tracked more than 300 cybersecurity M&A deals so far this year.
