“Site blocking makes pirates go legal”

3 Questions to Michael D Smith, professor at the Carnegie Mellon University

Can restricting access to pirate websites reduce internet piracy and does it influence legal sales? Many have suggested that the effect is small and that pirates will only move to a different service if one becomes unavailable. A fresh study from Carnegie Mellon University looked into the topic using the UK as guinea pig. Netopia talked to CMU Professor Michael D Smith.

Per Strömbäck: Does blocking pirate websites decrease online piracy?

Michael D Smith: It’s difficult to measure overall changes in piracy levels. What we can measure is how piracy changes for the sites affected by the blocks: The Pirate Bay in May 2012 and 19 additional piracy sites in fall 2013.

When The Pirate Bay was blocked, we saw an 80% reduction in visits to TPB among prior users, and for the 19-site block, we saw a 75% reduction in visits among prior users of those sites.

Why wasn’t there a 100% drop in visits? Three reasons. First, ISPs implemented the blocks over time — some immediately after the blocks were ordered, and some several weeks later. Unfortunately, we don’t know when the users in our data were affected by the block, only when first block occurred. So, to be conservative in our analysis, we assume that all the users in our data experienced the block immediately (even though many users experienced the blocks up to 4 weeks later). Second, when the sites were blocked, many users bypassed the blocks, using Virtual Private Networks, and those visits show up in our data. Third, some smaller ISPs did not implement the blocks and those users’ visits show up in our data.

But to us, the interesting question isn’t whether these blocks reduced piracy visits per se. The interesting question is whether it influenced legal consumption…

PS: Does it increase legal sales?

MDS: Initially, no — there was no statistical change in visits to legal streaming sites when only The Pirate Bay was blocked in May 2012.

However, there was a statistically significant increase in visits to legal streaming sites after 19 additional sites were blocked in fall 2013. After the 19-site block visits to legal streaming sites increased by 12% across all the users in our data. And, the increase was higher among those who previously were heavy users of the blocked sites (23.6% increase in legal site usage after the block occurred) than among the lightest users of the blocked sites (3.5% increase), suggesting that the increase in legal usage is causally related to the blocks.

PS: Don’t internet users find ways to by-pass the block? 

MDS: Yes. After the blocks were implemented, there were large increases in visits to other unblocked torrent sites, visits to unblocked cyberlocker sites, and in the usage of VPN services. As academics studying consumer behavior, we find it interesting that even though there were many ways to get around the blocks, when users found it hard enough to find new pirate sites (i.e., after the additional blocks of 19 prominent piracy sites), many former pirates switched from piracy to legal consumption.