The world's largest Internet service provider believes spammers are starting to give up -- at least when it comes to sending junk to its subscribers.
The total number of e-mail messages destined for America Online Inc members averaged 1.6 billion last month a day, down from 2.1 billion daily a year earlier, the company said on Monday.
The drop was almost entirely in spam, AOL said.
AOL spokesman Nicholas Graham attributed the drop largely to spammers moving on after realizing that many of their messages won't get through AOL's anti-spam filters or that they might get sued for trying.
During the same period, the number of spam complaints from members dropped more than 75 percent, after adjusting for a decline in subscribers. AOL had 22.7 million US subscribers as of September, compared with 24.7 million a year earlier, according to the latest regulatory filings by parent Time Warner Inc.
AOL also has seen declines in spam messages deleted at AOL's gateways as well as those diverted to spam folders by filters under the control of AOL members.
Officials at Yahoo Inc, EarthLink Inc and Microsoft Corp did not respond on Monday to requests for statistics for their services.
Postini Inc, a company that handles e-mail filtering for more than 4,000 companies including smaller Internet service providers, said it has noticed a shift toward spamming smaller networks.
small firms targeted
"Smaller companies get more spam per person than big companies do," said Andrew Lochart, director of product marketing. "If you're a spammer, you're going to assume that somebody who's a Fortune 500 company has good defenses against [this] stuff, and you're not likely to bother."
But overall, the spam threat was level, if not increasing. In any given month, spam continues to account for 75 percent to 82 percent of all messages routed through its system, Lochart said.
John Levine, an anti-spam advocate, said AOL deserves credit.
"They really do have fabulous spam filtering doing a fair amount of good," Levine said.
He added that AOL helped build a case that led to the conviction of one of the world's most prolific spammers, Jeremy Jaynes.
A state jury in Leesburg, Virginia, has recommended a nine-year prison term in the first felony trial of spam purveyors in the US. Sentencing is scheduled for February.
"AOL put a guy in jail," Levine said. "If I were a spammer, I would say, `Gosh, the cops would throw me in the slammer.'"