Beginning today, Yahoo Mail will begin filtering spam into separate folders, according to Geoff Ralston, vice president of Yahoo's communications group. The software, which was created internally, will automatically determine whether email being sent to a user is unsolicited and then take appropriate action.
"We have an automatic system that can see all messages that come into Yahoo Mail and uses technology to determine whether something is spam or not," he said in an interview.
Ralston declined to elaborate on how the system works, citing concerns that spammers could exploit the filter. He also declined to comment on whether the technology will be patented and marketed to other email systems.
Whether the company's filter will succeed is an open question.
Spam may be the most reviled byproduct of the Internet, sparking outrage among many Net users: Internet service providers say spam overburdens their servers, privacy advocates say spam marketers trample privacy rights, and Net users hate having their email in-boxes filled with unwanted email.
Several states have enacted legislation to curb the proliferation of spam, and ISPs such as America Online have filed lawsuits to stamp it out.
Still, it has proven impossible to eradicate.
Spam accounts for about 10 percent of all email traffic--a figure that has remained about constant even as Internet usage has spiked, according to John Mozena, co-founder and vice president of the Coalition Against Unsolicited Commercial Email (CAUCE).
So far, at least, filters have not been widely regarded as a solution to the problem.
This month, Microsoft's free email provider Hotmail came under fire for instituting a controversial anti-spam filter, blocking mail from servers on the Mail Abuse Prevention System (MAPS) Realtime Blackhole List (RBL). The list is composed of email servers known to be used by senders of unsolicited commercial email, or "spammers."
Even after Hotmail installed the filter, however, users noticed no difference in spam intake.
There are distinct differences between Hotmail's and Yahoo's efforts to eliminate spam from their services. Hotmail's filter blocks a set list of domain names that allegedly send unsolicited offers to email users, whereas Yahoo's relies on its technology to separate the junk.
Despite the risks of filters, however, some anti-spammers applauded the moves by Yahoo and Microsoft as a step in the right direction.
"Spam filtering is always a trade-off between missing stuff you want and getting stuff you don't want," said Jason Catlett, president of Junkbusters, a clearinghouse for privacy-protection measures. "Every company is going to make some mistakes along the way, but I think it has to be done. To not filter at all is just leaving too many doors unlocked in a bad neighborhood."