Sophos today reported a large leap in its annual revenues, in notable contrast to wider economic concerns.

The security firm said in its year-end results that so-called 'billings' were up 28% year-on-year to $213.9m. It refers to billings as the total of products and services invoiced and it uses this figure instead of reporting straightforward revenues.

The company said it won 259 new contracts worth over $100,000 in the last twelve months, claiming most of those were won from Symantec or McAfee. Its greatest successes have been in North America and Japan, the company said.

Sophos last week won praise from influential analyst firm The 451 Group. Its research director Nick Selby said Sophos - along with other second tier vendors like AVG, BitDefender and Kaspersky - were making inroads into the market share of Symantec and McAfee, who are the market leaders.

Speaking at a conference organised by The 451 Group, Selby said Sophos had recently won an account from Symantec for thousands of desktops at General Electric. "They said the service is better," said Selby on Thursday.

Meanwhile, Sophos appears to be gearing up for another attempt at an IPO - when the markets improve.

Quoted in the Financial Times today, its chief executive Steve Munford said Sophos "would consider listing on Nasdaq or London when markets stabilised".

Sophos had tried to raise £100m through a placing last November, but had to back down because of financial worries in the technology sector.

The Oxfordshire-based firm is currently the world's largest security company still under private ownership. It now boasts 20 consecutive years of revenue growth.