Spam Worries Google Advertisers
Google is on the lookout for "impression spam"
but denies it poses a big threat to paid search advertisers.
Advertisers and SEM firms beg to differ.
The search engine giant defines impression spam as "ad
impressions generated outside of normal search activity,
in some cases deliberate in other cases not deliberate,"
whose overall effect is minimal, said Salar Kamangar,
Google's director of product management.
Paid search advertisers like Richard Leino, the founder
of WebsiteMaven.com, disagree about the "minimal"
part. Because Google takes click-through-rate (CTR)
into account when it decides the rankings of search
ads, extra impressions without click-throughs can result
in an ad being demoted or even disabled. (Overture does
not use CTRs to determine the ranking of its paid search
Advertising on "Web hosting" was Leino's introduction
to the effects of impression spam. In the last 10 months,
Leino periodically noticed bursts of ad impressions
over 10 times higher than the typical daily average
on the keyword.
"I've seen acts of God, hurricanes on the keyword,
with over 100,000 impressions in a 12-hour period on
a term that typically gets 8,000 impressions a day,"
Industry-watchers speculate fraudsters take advantage
of Google's system by disabling their own ads, making
a flurry of queries on their chosen keywords, and then
re-enabling their ads. By doing this, they drive down
the CTR on competitors' listings, then swoop back in
to claim higher rankings.
"I've had consistently good click-through rates
for the last 10 months, but periodically you see all
your efforts get wiped out in a matter of hours, and
you have to increase your cost per click to get back
on top," Leino said.
Leino estimates impression spam has cost him a total
of $1,000 to $2,000 in the last 10 months, because he
had to pay more to keep a higher ranking and potentially
lost business when his ad ranking went down. That amounts
to between five and 10 percent of his total revenues
during that time period.
Google has gotten increasingly vigilant about dealing
with Leino's impression spam problem, he said.
"Google initially told me there was nothing that
could be done about it, but a few months later did erase
the false impressions, which improved my click-through
rate," Leino said. "The problem is it keeps
For Lisa Wehr, president of SEM firm Oneupweb, incidents
of impression spam like the one Leino experienced call
into question the logic of Google's CTR-based ad-ranking
"It's further evidence that if there is a chink
in the armor, it will be exploited," Wehr said.
"This is where Google needs to review what they're
doing. Without the CTR algorithm, impression spam would
But Kamangar defended the value created by its CTR-based
ad ranking system for both search engine users and advertisers.
"Our ad ranking system ensures that the most relevant
ads will be seen by the users of our search engine,"
he said. "It's good for advertisers because it
prevents advertisers from dominating a narrow field
simply by paying a higher cost per click."
Gauging the prevalence of impression spam is another
thorny problem, said Gordon Brott, VP of marketing for
WhosClickingWho, a business that identifies and stops
"As far as we can tell, impression spam is not
nearly as widespread as click fraud," Brott said.
"But it's probably safe to say that the problem
is going to get bigger."
Google, however, doesn't expect incidents of impression
spam to escalate, Google's Kamangar said.
"We have an automated system in place that detects
when unusual amounts of impressions are occurring without
click-throughs," Kamangar said. "And we have
a team of analysts in place to research cases that are
reported to us. It's a mechanism that grows more sophisticated
over time and one that is working. So we do not expect
an increase in the number of incidents in the future."
Back to Archive >>