Google put down 21,000,000 infringing links copyright holders asked them to remove from the search engine list in 2013. It is 9% of the total of 235,000,000 links submitted to Google this year. The 9% amounts to 21 million URLs for which Google decided not take any action because many were duplicates and others were illegitimate. Fox, Lynda.com and NBC Universal have more than a quarter of their requests denied by the search engine giant.

In 2011, Google received less than 10 million URLs from removal from its search engine. However, in 2012 it grew to more than 50 million. In 2013, the requests quintupled, and Google was asked to remove more than 235 million URLs.

TorrentFreak reported that the music industry tops the list along with anti-piracy groups like RIAA and BPI. They have sent close to 41.7 and 30.8 million removal requests to Google. Twentieth Century Fox has submitted 19.3 million followed by Froytal Services - 19.2 million and Microsoft - 10.4 million.

Lynda.com is at the top when it comes to the highest percentage of request denial. Google took no action for almost 57% of the total URLs the company requested.

Also, Google discarded 28% and 25% of NBC Universal and Warner's requests, respectively.

However, there are institutions like The RIAA, BREIN and Adobe who have great track records. Google discarded only 2% of their requests.

Google keeps a close eye on the "no action" list.

"We still do our best to catch errors or abuse so we don't mistakenly disable access to non-infringing material. Google continues to put substantial resources into improving and streamlining this process, including into identifying erroneous and abusive takedowns, and deterring abuse," said Google.

On the other hand, copyright holders mentioned that Google must be proactive in their approach to curb infringing sites. For instance, the RIAA asked Google to initiate banning complete domains from the search results.

"Every day produces more results and there is no end in sight. We are using a bucket to deal with an ocean of illegal downloading," said Brad Buckles, RIAA executive vice-president.