The headlines are eye-catching. Melania Trump is leaving the White House! Home renovation cable star Joanna Gaines has abandoned her HGTV show and husband Chip Gaines! Televangelist Joel Osteen is leaving his wife!
None of the stories were true. Yet as recently as late last week, they were being promoted with prominent ads served by Google on PolitiFact and Snopes, fact-checking sites created precisely to dispel such falsehoods.
According to an examination by The New York Times, the enticing headlines served as bait to draw readers to fraudulent sites that masqueraded as mainstream news sites, such as People and Vogue.
The fake news ads all worked the same way: They would display headlines at the top of the fact-checking sites that, once clicked, took readers to sites that mimicked the logos and page designs of legitimate publications. The fake stories began with headlines and large photos of the celebrities in question, but after a few sentences, they transitioned into an ad for an anti-aging skin cream.
The fake publishers used Google's AdWords system to place the advertisements on websites that fit their broad parameters, though it's unclear if they specifically targeted the fact-checking sites. But that Google's systems were able to place fake news ads on websites dedicated to truth-squadding reflects how the internet search giant continues to be used to spread misinformation. The issue has been in the spotlight for many internet companies, with Facebook, Twitter and Google all under scrutiny for how their automated ad systems may have been harnessed by Russians to spread divisive, false and inflammatory messages.
The Snopes and PolitiFact ads show how broad the problem of online misinformation can be, said David Letzler, research scientist at Impact Radius, a digital marketing intelligence firm. ''Even websites whose mission is to promote accountability can inadvertently wind up getting used by snake oil salesmen,'' he said.
Google declined to explain the specifics of how the fake news ads appeared on the fact-checking sites. The accounts that advertised on Snopes and PolitiFact were terminated from Google's ad platform after The Times asked about them, according to a person with knowledge of the sites who asked to remain anonymous because the details were confidential.
''As always, when we find deceptive ad practices on our platforms we move swiftly to take action, including suspending the advertiser account if appropriate,'' Chi Hea Cho, a Google spokeswoman, said in a statement. ''In addition, we give publishers controls so they can block specific types of ads and advertisers.''
When alerted to the ads promoting untrue stories on their sites, Snopes and PolitiFact said there was little they could do. Google's AdSense, which is used by web publishers to sell display advertising on their sites, works through automated tools. Often, advertisers are unsure where their ads are running -- sometimes next to inappropriate or offensive content -- and site owners don't know which ads will appear on their pages.
Vinny Green, Snopes's co-owner and vice president, said it had tried to filter out misleading advertisements from the 150 million ads it displayed on its site last month. But that goes only so far.
''We have little direct oversight or control over what is being done to filter out fake news ads being served on our site,'' he said in an email. He added that the online ad ecosystem was complicit in disseminating and profiting off of misinformation, and that ''these ad quality problems are systemic.''
Aaron Sharockman, executive director of PolitiFact, said it was working with Google to remove the ''questionable text ads'' from its site.
''The revenue those advertisements provide is critical to funding a website like ours, but it's equally important that we do everything we can to make sure the advertisements appearing on our site are not deceptive or intentionally misleading,'' he said.
More from The New York Times:
Google, which sells more online advertising than any other technology firm, has struggled to prevent fraudulent websites from making money off the spread of false stories. Earlier this year, it touted its efforts to crack down on misinformation sites by kicking 340 websites and 200 publishers off its AdSense platform. Most of those publishers had created websites to peddle eye-catching but untrue political stories, and loaded up the pages to get a cut of advertising revenue from Google.
But the websites that advertised on Snopes and PolitiFact took a different approach. Those publishers paid Google to promote their content on legitimate websites to draw traffic for an ad pretending to be a news story, often carrying the banner of a mainstream news publication.
Google has called the process ''tabloid cloaking.'' It has said these types of scammers use timely topics and ads made to look like new website headlines. Google said it suspended more than 1,300 advertiser accounts in 2016 for tabloid cloaking. This month, Google said it had introduced additional controls to help publishers filter out sensational or tabloid ads.
The ad heralding the untrue story about Mrs. Trump's decision to leave Washington and the White House appeared at the top of PolitiFact last Friday. The display ad led to a fake Vogue news article claiming that the story was also featured on Yahoo, Vanity Fair and Time, among other publications.
On another PolitiFact page, there was another display ad promoting a false story about Mr. Osteen, the leader of Lakewood Church, a Houston-based megachurch, leaving his wife because she had said too much on TV. When clicked, the ad went to a fake Us Weekly page about how Mrs. Osteen was leaving the church to focus on her skin cream company.
The publisher of the fake Us Weekly site also bought a Google search ad, so that a query for the headline of the story ''Sad News For Lakewood Church'' linked to that same fake story.
In the case of the HGTV stars Joanna and Chip Gaines, the ad about the couple that ran on Snopes last week promoted a report that had been refuted already by the fact-checking site in an article a month earlier.
PolitiFact and Snopes are among the most influential and most popular fact-checking websites. Snopes was created in 1994 to debunk urban legends but has since evolved into a 16-person operation that also assesses political spin. PolitiFact, launched in 2007 as a service of the Tampa Bay Times, won a Pulitzer Prize for its work during the 2008 presidential election and has 14 state chapters in addition to a national operation.
Both PolitiFact and Snopes partnered with Facebook last December, after the social network was criticized for abetting the spread of fake news during the 2016 presidential election. Their experiment -- in which viral and popular posts debunked by the fact checkers are marked as ''disputed,'' and cannot be promoted in News Feeds -- expanded and became more aggressive in August.
Google, too, has attempted to dispel misinformation. Jigsaw, its tech incubator, developed a ''Share the Facts'' tool alongside the Duke University Reporters' Lab.
David Carroll, an associate professor at the Parsons School of Design who has researched advertising technology and fake news, said Google and Facebook ultimately don't know enough about their customers -- advertisers -- making it too easy to game the system without serious repercussions.
''For a few bucks, they allow anyone to target anyone else in the world,'' Mr. Carroll said. ''The whole ecosystem has been infiltrated, and there is insufficient friction to keep bad actors out of the system.''
Follow Daisuke Wakabayashi on Twitter @daiwaka and Linda Qiu @YLindaQiu