The second highest requester is NBCUniversal, which trails far behind Microsoft in the number of URLs it has request Google block. Between July 2011 and today, NBCUniversal asked Google to remove just more than 1 million URLs, or less than half of the number requested by Microsoft.

In contrast, the Recording Industry Association of America (RIAA), which is often perceived as being the biggest copyright cop on the Internet, asked for a mere 416,000 URLs to be blocked. On average, the RIAA or its agents put in about six URL removal requests per week compared to Microsoft's 169 requests per week.

The most targeted domains of such requests were filestub.com, torrentz.eu, 4sharesd.com and zippshare.com.

In the 3% of cases where Google did not remove URLs, it was because the removal requests were inaccurate or intentionally abusive, Google noted. As examples it pointed to a request by a major U.S. movie studio that requested the removal of the IMDb page for a movie released by the studio, and another instance where the representative of a movie studio asked for the removal of a movie review from a newspaper's website.

Google's copyright transparency report is important because it sheds light about the behavior of copyright holders and the organizations representing them, the Electronic Frontier Foundation .