Vendor lineage
Sophos
Started in Oxford the year before the first PC virus spread, and is still here under its own name.
Jan Hruska and Peter Lammer founded Sophos at Oxford in September 1985, writing virus detection for the IBM PC before most people had encountered a virus. The name is the Greek for wisdom, chosen to signal a research-led posture rather than a product one.
The early business was deliberately narrow: corporate and educational customers in Britain and Europe, largely self-funded, at a time when antivirus was a cottage industry of individual researchers trading samples. By the early 1990s it was protecting thousands of enterprise endpoints.
It expanded into encryption, then into unified threat management, and became one of the few security vendors whose product line spans endpoint and network without either half having been bought in late.
Sophos listed on the London Stock Exchange in 2015 and was taken private by Thoma Bravo in 2020 - the same firm that appears elsewhere on this timeline holding LANDESK before Ivanti, and Ping Identity before ForgeRock. It has since acquired Secureworks.
What makes it notable here is longevity of a specific kind. Almost every company on this page that started in the 1980s has ended inside another one. Sophos is forty years old, privately held, and still trading under the name its founders chose.