Many bloggers use non-Adsense Ad units in addition to Google AdSense or as an alternative to Google AdSense. However, some non-AdSense Adverts do have the risk of losing visitors by Redirection set by the Ad script.
Are you losing visitors through hijacking via redirection?
It is not uncommon. If you search the Internet you will get some names, we can not name any particular company for legal reasons that, who are responsible for losing visitors. Read the steps to diagnose in case of losing visitors.
Factors which might trigger these companies to steal your traffic and result you for losing visitors:

The above diagram of a particular dx/dt of losing visitors is supplied by a webmaster. He performed a real dx/dt at particular points, and was convinced it was not natural. He removed the Ads, as we can see there is an rise, he reintroduced to check again, however this time the loss was more rapid. The time frame of Losing Visitors shown above is in months.
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- Your traffic is targeted and from Search Engines
- Your Blog / website had a steady traffic at point x, then started to losing visitors at a rate which is gradually increasing.
- Your blog do have good content.
- The Advertisement company is CPM based, not a CPC type
Get back the losing visitors
Simply remove all Ad codes (except AdSense). Flush the cache manually. If possible do a restoration from backup, may be a sql restoration as well.
Wait for 5-7 days. You should be able to stop the rhythm of losing visitors.
Why these companies do so?
Think from a CPM Advertisement company’s point. CPM Adverts mean – more traffic more money, click is not so important. Why the Advertisers will pay if there is no traffic gain? Will you? No.
So, they take an indirect way to make money by redirecting the visitors.
