The company said on Wednesday it would offer an SLA to its customers guaranteeing that 95 percent of their spam would be blocked, with a false positive rate of less than 0.0004 percent.
MessageLabs provides an outsourced e-mail security service that filters all incoming messages before they reach the customer's internal network. The company claims it is the first to offer an SLA that guarantees to capture the majority of spam with a minute false positive rate.
Analysts said that MessageLabs' confidence in its products was a sign that the anti-spam market was finally getting on top of the problem.
Megan Dahlgren, senior analyst for software at International Data Corp (IDC), said although there is a greater volume of spam being sent, the technology used by anti-spam companies is now able to confidently identify unwanted e-mails.
"Catching spam is about identifying a certain class of e-mail. There are lots of different types of fish in the sea but if there was a huge growth of salmon, you would know the right type of net to catch the salmon. Similarly, spam is highly identifiable and easy to catch. It wouldn't be so easy if all the spam out there was different," said Dahlgren.
James Turner, security analyst at Frost & Sullivan, said companies had come to see e-mail as a commodity and so were more likely to pass over responsibility for separating legitimate e-mail messages from spam to a third party.
"For many companies e-mail is a business tool and very much a commodity service -- they are used to it. This is helping streamline that and it is a trend we are going to see a lot more of -- third parties stepping in and helping clean up the Internet. MessageLabs is taking responsibility away from the end user," said Turner.
IDC's Dahlgren said MessageLabs' SLA was more "a confidence and marketing thing than anything else. If you compare product for product they are pretty similar in the amount of spam they collect.
Joe Lombardo, marketing manager for MessageLabs Asia Pacific, said the company had always claimed to provide high levels of spam capture with a low false positive rate, but, following some independent testing last year, the company believed it was in a position to guarantee those levels.
"We have always been above a 90 percent capture rate but what we wanted to do was have an independent verification of it,' said Lombardo, referring to a test carried out by The VeriTest Anti-Spam Benchmark Service in November 2004.
"The testing coincided with us being able to go to market and say this is a level we can now guarantee," said Lombardo, who emphasised that MessageLabs already guaranteed its customers would not be infected by a virus, "We guarantee that firms will not be affected by any virus -- new or existing -- if they are using the MessageLabs service. This is just the next step."
Lombardo said that the spam SLA would apply to both existing and new customers and would not be part of a premium service. However, he was unable to state the amount of compensation that will be offered should the service fall below the agreed level.
"[Compensation] is on an individual basis but there is a credit that is offered on the service. We bill on a monthly basis so dependent on the level service degradation we would compensate on an individual basis," said Lombardo.