TWO Oxfordshire businessmen are set to become millionaires when their company floats on the London Stock Exchange Peter Lammer and Jan Hruska, who met when they were engineering research students at Oxford University in the 1970s, have built Abingdon-based Sophos into a global business providing IT security to 65,000 businesses in more than 125 countries, protecting an estimated 100 million computer users.

Revlon, Vodafone, Lockheed Martin, Heinz and Marks & Spencer are among clients who use Sophos software to combat threats such as computer viruses, spam, spyware, hackers and policy abuse.

Recent contract wins include GE, which has bought Sophos's Endpoint Security and Network Access Control for use on up to 350,000 of its computers.

The new product protects the customer from viruses and hackers by securing the desktop computer, rather than just the corporate network.

Sophos is planning to raise £100m to market this software in the US, and is likely to be valued at £300-500m, with the company founders and existing shareholders selling substantial holdings.

If Sophos can beat the turmoil in global stockmarkets, employees could also reap a windfall - spokesman Graham Cluley said a share-purchase scheme had been set up for staff, and share options had also been awarded.

Dr Lammer and Dr Hruska were among the first people in the world to market anti-virus software. The company started in 1985 in Dr Hruska's house in Kidlington and later moved to Haddenham. Sophos moved to Abingdon in April 1990 with six staff.

Now it has 13 offices worldwide with about 1,115 employees, of whom more than 520 are based in the £32m headquarters opened by the Queen at Abingdon Science Park in 2004.

Chief Executive Steve Munford said: "Becoming a listed public company is a natural next step in our development.

"The demand for our solutions continues to grow, and listing will enable us to maximise our profile and take better advantage of the current exciting opportunities within our market."

The founders are now likely to shoot up the Sunday Times Rich List, which last year estimated that they had paper fortune of £90m each, putting them in 725th and 726th place.

Sophos has won several Queen-s Awards for Enterprise and the founders were joint winners of the Oxfordshire Business Person of the Year in 2002.

No date for the flotation has yet been made public.