CEO Enrique Salem told ComputerWire that 70% of BrightMail’s new business came from the enterprise market in December, compared to 5% in January 2002. As the amount of spam slowly threatens to outweigh the amount of legitimate email, more companies are becoming interested in spam filters.

With the renewed focus on the enterprise, BrightMail is currently talking to a number of unnamed security appliance vendors about OEM deals, and has just ported its software to Linux to make such a transition easier, Salem said.

The private San Francisco-based firm, which is 12% owned by Salem’s alma mater Symantec Corp, has $20m in the bank, is also eying a possible IPO towards the back half of the year, once market uncertainly has hopefully subsided, Salem said.

BrightMail’s primary method of detecting spam is with fingerprints of unsolicited mail received by its probe network of thousands of dummy email accounts. But the latest enterprise edition also uses white lists, black lists, and some linguistic analysis.

But BrightMail’s Salem said he thinks buyers have to be wary of relying too much on heuristics – complex algorithms designed to detect spam based on prior linguistic analysis of what spam looks like.

When you deploy anti-spam technologies based on pattern recognition you’re going to make mistakes, so you’ve got to be careful, said Salem. You can’t afford to hire administrators to chase false positives in this economy or at any other time.

A low incidence of false positives is arguably a more important metric than percentage of spam caught. Deleting large quantities of spam may be annoying, but it’s not as annoying as not receiving a business-critical email.

Even a quarter of a percent [false positives] is unreasonable, Salem said. BrightMail says its version 4.5 software catches 92% of spam, but has a false positive ratio of one in a million, or about 0.0001%.

The company estimates that for an enterprise that pays its techies $80k a year and receives 100,000 emails a day, a 0.25% false positive rate means the firm is paying $833 per day just sorting out problems caused by spam filters, rising to $3,333 per day at 1%.

BrightMail says its new software, priced at $5 to $15 per seat, also features quicker integration with Exchange, automatic incremental (rather than batch) rule updates every 10 to 15 minutes, reports on mail and spam volumes, and monitoring for the denial-of-service impact of large spam attacks.

Source: Computerwire