New targeting ads pirates privacy?
Rakuten, No.1 EC company in Japan, has launched a new targeting ads system, "Rakuten Ads 4U." a couple months ago.
This ads system collects and analyzes user's web history, not only from its own ads network, but from all the web site.
The technique is pretty unique, or I should say, "violate".
They put thousands of external links on their flash embed components, and check if the users had ever visited each of the external links by obtaining the "visited" style sheet property.
This is thought to be a kind of bugs of the css and javascript specification.
I admit they are wise enough to cheat this feature, but this would be a piracy for the user's privacy, and I believe they should not use this technique to do better targeting ads delivery.
I should list up all the web sites they are sneaking into our web history to grab our preferences...