Prevx

Prevx was a UK-based cybersecurity company that developed anti-malware software. It was originally founded as Immunify in March 2001 by a team led by CEO Nick Ray and COO Paul Stubbs. The company rebranded to TrustCorps later in 2001 and finally became Prevx in 2003.

Initially, the firm focused on creating a Host Intrusion Prevention System for UNIX/Linux servers, designed to offer protection from unknown, or "Zero-Day," threats without relying on traditional malware signatures. This early software monitored the real-time behavior of executables and blocked system calls that violated its security rules, providing a last line of defense against threats like buffer overflow attacks and rootkits. In 2005, Prevx was acquired by Retento Limited, an investment vehicle owned by serial entrepreneur Mel Morris, who had joined the board in 2003. Morris, who also founded the dating site Udate and was an early investor in King, the creator of Candy Crush Saga, became the CEO of the newly named Prevx Group Limited.

Under Morris's leadership, the company shifted its focus to the Windows platform, launching its first freeware product, Prevx Home, in 2004. The business operated on a freemium model, allowing free removal of low-risk adware while requiring a paid license for more serious threats. Its core technology was a small, fast, and light security agent (under 1MB) that communicated with a massive cloud-based threat database. This behavior-based detection was faster and more effective than traditional signature-based antivirus products. Products included Prevx 3.0, Prevx Edge, and Prevx CSI, which provided real-time protection for home PCs and corporate networks. In November 2010, the Derby-based Prevx was acquired by the US internet security company Webroot. Webroot integrated Prevx's cloud and behavioral analytics technology into its own security products, and Mel Morris became the vice president of Webroot's new Prevx division. Webroot has since discontinued the Prevx product line, but its underlying technology continues to be a part of Webroot's security offerings.

Keywords: anti-malware, cybersecurity, behavior-based detection, cloud security, endpoint security, intrusion prevention, zero-day threat protection, malware removal, host intrusion prevention, rootkit detection, Webroot acquisition, Mel Morris