Enterprise cybersecurity giant Proofpoint announced on Thursday that it’s acquiring Germany-based Hornetsecurity, a company specializing in Microsoft 365 security solutions.
Financial terms of the deal have not been officially disclosed, but CNBC reported that Proofpoint is acquiring the European competitor for $1 billion. SecurityWeek has asked Proofpoint for confirmation on the amount, but the company did not immediately respond.
SecurityWeek has learned that external sources close to the matter speculate that the deal size well exceeds $1 billion.
Hornetsecurity provides Microsoft 365 security, email security, data protection, compliance, and security awareness solutions.
The company claims to have an international distribution network that includes over 12,000 MSPs and channel partners, through which its solutions have reached more than 125,000 customers.
Proofpoint said the acquisition of Hornetsecurity enables it to boost human-centric security capabilities, particularly for SMBs. The company provides email security, user protection, impersonation protection, enterprise data loss prevention, insider threat management, data security posture management (DSPM), and security awareness products.
The security giant also pointed out that Hornetsecurity brings in an annual recurring revenue (ARR) of more than $160 million.
Proofpoint announced several acquisitions in recent years. In 2022, it bought Illusive Networks, a startup that created deception technology for detecting data breaches, and Dathena, a Singapore-based company that specialized in data protection.
In 2023 it acquired Tessian to boost its ability to detect and block risky user behaviors, and in 2024 it acquired DSPM company Normalyze.
An analysis conducted by SecurityWeek showed that a total of more than 400 cybersecurity-related mergers and acquisitions were announced in 2024.
*updated with information on deal size estimation
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