We explain how ads work on the web and why it’s hard to stop fake ones

• Web portals have limited options against misleading advertising.
• Google decides which ad is displayed where. However, fake advertisers are often more sophisticated than its tools.

“No one believed what Ivan Korčok did live,” says an advertisement with a photo of the former diplomat on Denník N’s website. And this is not the only case – the advertisement, which abuses the faces of well-known personalities, is displayed all over the Slovak Internet. It often leads to fake websites that closely resemble media sites such as Aktuality.sk or Denník SME.

Administrators and website owners are contacted daily by readers and sometimes representatives of well-known personalities who have appeared in them involuntarily with warnings about suspicious banners. However, it is almost impossible to fight against this problem.

“Advertisers use hundreds of accounts and URL addresses that have similar content,” explains Tomáš Kálmán, business director of Denník N. “This means that when we block one fake ad, another, very similar, but from a different address appears immediately.”

Web visitors can also help

Advertising spaces on websites such as Denník N are served by external automatic marketplaces, such as the Google Display Network. Websites thus have only a limited influence on what ads are displayed on them, they can only retroactively block specific advertising.

On the pages of Denník N, in addition to the front page, there are also a number of sub-pages with separate advertising banners. In addition, each visitor may be shown a different ad.

It is therefore best if the reader