ALBANY, N.Y. - Unwanted software slithered into Patti McMann’s home computer over the Internet and unleashed an annoying barrage of pop-up ads that sometimes flashed on her screen faster than she could close them.
Annoying, for sure. But the last straw came a year ago when the pop-ups began plugging such household names as J.C. Penney Co. and Capital One Financial Corp., companies McMann expected to know better.
Didn’t they realize that trying to reach people through spyware and its ad-delivering subset, called adware, would only alienate them?
‘‘It irritated the heck out of me,’’ said McMann, a 45-yearold former corporate executive from Klamath Falls, Ore. ‘‘It took a week to take off every little piece that was put on my computer. Every time I rebooted, it started to come up again.’’
Pop-up ads carried by spyware and adware aren’t just employed by fringe companies hawking dubious wares — such as those tricky messages that tell you your computer has been corrupted.
You can count some big tech companies among its users, including broadband phone provider Vonage Holdings Corp., online employment agency Monster Worldwide and online travel agencies Expedia, Priceline.com and Orbitz LLC.
These companies acknowledge they’ve used adware to reach potential customers, though they say they shun programs that monitor surfing or extract personal information.
Even Fortune 500 companies have turned to adware: Sprint Corp. for its PCS mobile phones, major banks peddling Visa credit cards, Sony Corp. and retailers including Circuit City Stores. And Mercedes-Benz USA had its cars flashing on consumer’s computer screens before the company, fielding complaints, put on the brakes.
Attempts to reach officials at J.C. Penney and Capital One about their use of adware popups were unavailing. Neither returned calls for comment.
Spyware and adware often land on computers without their owners’ full knowledge, hitching a ride during visits to porn and gambling sites or in downloads of free games and screen savers. Often, the payload arrives with downloads of cartoon-character wares aimed at children.
Infected computer users can get barraged with pop-up ads and find the unwanted programs difficult to remove.
So far, law enforcement has mostly targeted the transmitters. Intermix Media has agreed to pay $7.5 million in a tentative settlement of a lawsuit by New York Attorney General Eliot Spitzer.
But Spitzer isn’t stopping there. He is threatening to hold accountable householdname advertisers that use adware networks. No longer, says Spitzer, can companies play dumb.
That’s making many advertisers nervous, though they insist they work with subcontractors and often don’t know about any adware use until they get a complaint.
‘‘There’s plausible deniability at each tier,’’ said Chris King, product marketing manager at antispyware vendor Blue Coat Systems.
Big-time online advertising is built on layers: A big advertiser, such as a Fortune 500 company, directs an agency to handle a campaign. The agency then farms that message out to specialists in various media, which can include spyware and adware purveyors.
‘‘We do everything we can to make sure our partners adhere to our standards,’’ said Jeffrey Citron, Vonage’s chief executive.
Yet a pop-up ad for Vonage appeared in a screen shot that Spitzer used in his case against Intermix. Citron said he was unaware of the ad and promised to look into it, as he said the company does with similar complaints.
Mercedes-Benz says its ad was carried to hard drives last year by an agency it has since fired, while computer maker Dell USA has fired ‘‘a handful’’ of affiliates for carrying Dell’s coupons and ads over adware.
‘‘This is not a practice we condone,’’ said Dell spokeswoman Jennifer Davis.
Dave Methvin, chief technology officer with tech diagnostic site PC Pitstop, said problems are no surprise given the many layers involved, but big advertisers have the clout to stop them.
‘‘If you’re going to be a good corporate citizen, part of your responsibility is to make sure that kind of thing doesn’t happen rather than to say it’s three levels down,’’ Methvin said. ‘‘If a big company advertising on the Internet makes all of its suppliers down the chain sign a statement (and agree to penalties for breaking the rules), quickly the problem would go away.’’
It’s not just big advertisers who have ties to spyware and adware.
Yahoo made a deal with adware company Claria Corp., formerly known as Gator Corp., to provide search listings for its SearchScout toolbar. The popular search engines Ask Jeeves and Google also benefit from adware, says Internet researcher Benjamin Edelman.
He says an Ask Jeeves toolbar generates ads without users’ full consent, while Google’s search listings appear in queries made through a questionable third-party toolbar. Ask Jeeves and Google officials dispute Edelman’s account and say they don’t use any spyware or adware. Company policy bans the use of adware by Google, said spokesman Barry Schnitt.
Several states have adopted antispyware laws, and the U.S. House approved two bills in May that carry jail sentences of up to five years in prison. The bills, which don’t target advertisers, are now before the Senate, where similar legislation died last year.
While Spitzer and some lawmakers in Alaska, Pennsylvania and Utah say advertisers should also be held accountable, not everyone agrees.
‘‘So many people have such antipathy toward adware and spyware vendors that it blinds them to the underlying legal principles,’’ said Eric Goldman, a cyber law professor at Marquette University.
He said any liability would be unprecedented and would be akin to holding an advertiser responsible for libel by the newspaper in which the ad appears.
Some advertisers defend the practice.
‘‘It is just a marketing tool that we use,’’ said Expedia spokesman David Dennis.
Expedia, like many other adware users, insists it has rigorous standards and checks to make sure customers want their ads and can easily remove the software if they don’t. Dennis said the company works closely with its ad agencies to make sure.
Melinda Tiemeyer, spokeswoman for Sprint PCS, said Internet users have clicked on ads delivered by adware, meaning they find them useful. Sprint is OK with using adware because users, she said, accept it in exchange for phone service offers and discounts.