Proofpoint to acquire Hornetsecurity in move to expand Microsoft 365 threat protection

Cybersecurity firm Proofpoint Inc. today announced it plans to acquire Hornetsecurity GmbH, a Germany-based pan-European provider of artificial intelligence-powered Microsoft 365 security, data protection, compliance and security awareness services.

The price of the acquisition was not officially disclosed, but CNBC reported that the deal was north of $1 billion.

Founded in 2007, Hornetsecurity’s flagship offering, called 365 Total Protection, offers a suite designed to secure Microsoft 365 users against threats like spam, phishing, malware and ransomware. The offering includes advanced features such as AI-powered threat detection, email encryption and compliance filtering tailored for enterprise needs.

In addition to threat protection, Hornetsecurity provides email continuity and archiving solutions that ensure uninterrupted email access during outages and maintain secure, legally compliant archives for long-term data retention and audit readiness.

Another product offering from the company, 365 Total Backup, delivers reliable backup and recovery for Microsoft 365 emails, contacts, calendars, OneDrive and SharePoint, allowing organizations to quickly recover from things such as accidental deletions, ransomware attacks, or system failures.

For Proofpoint, the acquisition of Hornetsecurity will enhance its ability to provide human-centric security to small and midsized businesses globally through managed service providers, further enabling all organizations to protect their people and defend their data.

In a positive, particularly given that Proofpoint is working toward going public in 2026, Hornetsecurity also brings impressive numbers to the table. The company provides solutions to more than 12,000 channel partners and MSPs and more than 125,000 small and midsized businesses across Europe and notably has more than $160 million in annual recurring revenue with over 20% year-over-year growth.

“As attackers grow more sophisticated and people remain the primary target, organizations need security that protects them wherever they work – across email, cloud applications and every digital channel,” Proofpoint Chief Executive Sumit Dhawan said in a statement. “We look forward to deepening our investment in the European markets as part of our global growth strategy.”

Coming into its acquisition, Hornetsecurity had raised six rounds of funding, according to Tracxn, but the amounts raised between a seed round in December 2007 and the company’s Series C round in September 2022 were not disclosed. Investors in Hornetsecurity include TA Associates Management, PSG Equity, Verdane Capital Advisors AS, Neuhaus Partners GmbH and High-Tech Gründerfonds Management GmbH.

The acquisition follows in the footsteps of other notable cybersecurity acquisitions this year, including Google LLC’s announcement in March that it plans to acquire Wiz Inc. for $32 billion and Palo Alto Networks Inc.’s buy of Protect AI Inc. reportedly for more than $500 million in April.

Photo: Hornetsecurity