Dive Brief:

• The online ad industry has an almost under the radar challenge: ad injection. 
• Ad injectors are computer programs that insert ads into Web pages where they don't belong — usually from a downloaded toolbar or other browser add-on. 
• Google has received over 100,000 complaints of ad injections since the beginning of this year. 

Dive Insight: 

With the injected ads, the advertisers and publishers lose control over what appears on the pages. The good news is that Google and other advertisers are working to crack down on the practice. Through research, Google was able to identify that 77% of ad injections were coming from three major ad networks and is sharing that message with advertisers.