Enterprise cybersecurity giant Proofpoint has completed the acquisition of Germany-based Microsoft 365 security solutions provider Hornetsecurity.
Financial details were not officially disclosed when news of the transaction came to light, but it was reported that Proofpoint would be paying $1 billion for its European competitor. SecurityWeek learned at the time that the deal size well exceeded $1 billion.
Proofpoint has now revealed that the transaction has been valued at $1.8 billion.
Through the acquisition of Hornetsecurity, Proofpoint is aggressively expanding its reach into the SMB market and strengthening its foothold in Europe.
Hornetsecurity will operate as a dedicated business unit focused on MSPs. The company serves more than 12,000 MSPs and 125,000 customers.
Hornetsecurity founder and CEO Daniel Hofmann will lead this new unit as Executive Vice President and General Manager.
In terms of finances, Proofpoint said Hornetsecurity brings in nearly $200 million in annual recurring revenue, with a 20% year-over-year growth rate.
“[Hornetsecurity’s] flagship software platform, 365 Total Protection, is a comprehensive, cloud-native solution that gives MSPs a clean, integrated way to secure Microsoft 365 environments,” said Sumit Dhawan, CEO of Proofpoint.
“It complements Proofpoint’s enterprise-grade solution, and together we can now protect people, data, and AI agents for every customer, across enterprises and small businesses,” Dhawan added.
SecurityWeek’s cybersecurity M&A tracker has cataloged roughly 400 deals to date in 2025. An analysis of this year’s mergers and acquisitions will be published in early 2026.
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