Proofpoint to acquire European cloud security firm Hornetsecurity for over $1 billion

The cybersecurity giant Proofpoint announced on Thursday that it plans to acquire the German firm Hornetsecurity in an effort to extend its footprint in Europe and boost its security offerings for managed service providers (MSPs) who work with small and mid-sized businesses.

Founded in Hanover in 2007, Hornetsecurity has $160 million in annual recurring revenue and more than 20% year-over-year growth, according to a news release about the acquisition. The deal is valued at “well over” $1 billion, according to a source familiar with the acquisition, though the exact terms of the agreement are confidential.

It would mark the largest acquisition in Proofpoint’s history — which itself was acquired by private equity firm Thoma Bravo for $12.3 billion in 2021 — and one of the largest cybersecurity deals in recent years. 

With more than 125,000 customers, Hornetsecurity’s flagship product focuses on protecting companies from cyberattacks and other risks associated with Microsoft 365 — a top target for hackers given the software’s ubiquity. Hornetsecurity’s 365 Total Protection platform provides services including advanced email security, access and permission control and domain fraud protection for organizations who use the Microsoft toolkit.

"With the breadth of human-centric risks only growing, joining Proofpoint is a natural next step in our journey to build the strongest global offering of M365 security services,” said Hornetsecurity CEO Daniel Hofmann.

In Proofpoint’s press release about the deal, CEO Sumit Dhawan said the company was “deepening our investment in the European markets as part of our global growth strategy.”

The acquisition is expected to close in the second half of the year, and Hofmann will continue to lead Hornetsecurity along with the company's current management team. 

Large cybersecurity acquisitions have continued to ramp up as the appetite for IPOs has gone cold. In March, Google announced it was buying cloud security provider Wiz for $32 billion. In April 2024, Thoma Bravo said it would buy U.K.-based Darktrace in a deal valued at more than $5 billion. A month before that, Cisco closed a $28 billion deal to acquire Splunk.