As of April, 23 2015 00:00:00 GMT
Torrent Indexer scans public torrent sites. A list of torrents can be downloaded from it.
N=23,001,195 - number of torrents in the Torrent Indexer's list
Currently TorrentTags is based on the Chilling Effects information. Chilling Effects Clearinghouse collects DMCA notices which were sent to websites. Every DMCA notice contains some URLs. If a URL has a hash inside, this hash will be added to the TorrentTags database.
TT=2,801,309 - number of torrents from N that have claims in the TorrentTags database.
Torrent Indexer accepts DMCA notices and publicly provides information about the total number of torrents deleted from its list due to these notices.
R=2,325,656 - number of torrents removed by Torrent Indexer from its list due to DMCA notices
From the Google transparency report:
G=4,092,099 - number of links to the Torrent Indexer which were sent to Google to be removed from the Google index
M=5% - URLs requested to be removed as a maximum percentage of the Torrent Indexer's indexed URLs.
In the following calculations we use the M value, so all of the following values are estimated maximum.
P=M*R/G=2.84% - proportion of number of torrents which Torrent Indexer removed from its list due to DMCA notices
T=N/(1-P/100)=23,673,923 - total number of torrents on the Torrent Indexer
E=100*TT/T=11.83% - proportion of torrents claimed elsewhere
The portion of claimed content from total number of torrents is equal to 14.67% (estimated maximum) as the sum of P and E.
Therefore only a small portion of all torrents is claimed. Hence, it is likely that these a large proportion of the content these public torrent sites host does not infringe copyright and blocking them has disallowed users from accessing non-infringing content.