Targeted banner - a weapon of modern headhuntera

Today, my friend, the head of one of the major St. Petersburg studios, spoke about the new method of dropping staff.
The other day, he unexpectedly discovered that when visiting from the office of most news resources, a banner of his competitors was shown inviting him to work.
Having estimated the amount of the advertising budget, he became suspicious and went to the sites via another IP address.

On all advertising places there were banners of usual advertising campaigns.
And when entering from the office IP, the banners changed and were invited to work for a competitor. In principle, technologically nothing new - the usual targeted by IP-address shows.

IMHO, this method of dropping personnel has great promise.

It is easy to calculate the competitor's IP address.
It’s also easy to set up IP targeting in an advertising campaign.
In principle, it is even possible to calculate a specific person and show
banners only for him and with a specific proposal - “Aftandil, come to us to work. We have your favorite buns. ”
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It is clear that the easiest way to implement such an event online advertising agencies, or include such a mini-advertising campaign in a large.

PS Who wants the details of the story in detail and with pictures - see here .