The European Commission (EC) is evaluating whether to extend existing data protection laws covering spam because of the economic toll that the practice is taking.
Users in individual European Union countries currently use either an 'opt-out' system where they tick a box if they do not want to receive unsolicited commercial emails, or 'opt-in', where they submit a request to receive information from third parties.
But following a study, commissioned by the EC, which revealed that such unsolicited commercial emails cost European surfers 10bn euros ($6.4bn) each year in connection costs alone, the organisation has signalled its belief that an opt-in system may be better for the industry and may boost consumer confidence in ecommerce.
A commission statement said: "This [opt-in] is supported by the study, which found that, from the point of view of industry, permission-based marketing is proving a more effective and viable method of data collection. The study also found that the opt-in approach would serve to bolster consumer confidence in the EU."
Currently, such a system is only in place in Austria, Denmark, Finland, Italy and Germany.
The EC had already indicated in July last year that it favoured making the opt-in system obligatory under data protection legislation. Such a move would effectively outlaw spam by 2002.
Spam-filtering firm Brightmail also confirmed that spam was costing businesses billions of pounds in downtime. Phil Fraher, the firm's chief operating officer, said: "Not only do these attacks result in an estimated 15 to 20 percent decrease in employee productivity, they also create huge downtime problems for ISPs, resulting in 'denial of service' for subscribers."
"American figures show that without effective spam protection, spam attacks may increase by as much as 150 per cent on a month on month basis," he added.
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