Chilling Effects is the largest public repository of DMCA notices on the planet, providing a unique insight into the Internet's copyright battles. However, each month people try to de-index pages of the site but Google has Chilling Effects' back and routinely rejects copyright claims.

Each week many millions of DMCA-style copyright notices are sent to sites and services around the planet. Initially the process flew almost entirely under the radar, with senders and recipients dealing with complaints privately.

In 2001, that began to change with the advent of Chilling Effects, an archive created by activists who had become concerned that increasing volumes of cease-and-desist letters were having a “chilling effect” on speech.

In the decade-and-a-third that followed the archive grew to unprecedented levels, with giants such as Google and Twitter routinely sending received notices to the site for public retrieval.

However, while Chilling Effects strives to maintain free speech, several times a month rightsholders from around the world (probably unintentionally) try to silence the archive in specific ways by asking Google to de-index pages from the site.

As can be seen from the tables below, Home Box Office has tried to de-index Chilling Effects pages 240 times, with Microsoft and NBC Universal making 99 and 65 attempts respectively.

The ‘problem’ for these copyright holders is two-fold. Firstly, Chilling Effects does indeed list millions of URLs that potentially link to infringing content. That does not sit well with copyright holders.

“Because the site does not redact information about the infringing URLs identified in the notices, it has effectively become the largest repository of URLs hosting infringing content on the internet,” the Copyright Alliance’s Sandra Aistars complained earlier this year.

However, what Aistars omits to mention is that Chilling Effects has a huge team of lawyers under the hood who know only too well that their archive receives protection under the law. Chilling Effects isn’t a pirate index, it’s an educational, informational, research resource.

Thanks to Google, which routinely throws out all attempts at removing Chilling Effects URLs from its indexes, we are able to see copyright holder attempts at de-indexing.

Earlier this month, for example, Wild Side Video and their anti-piracy partners LeakID sent this notice to Google aiming to protect their title “Young Detective Dee.” As shown below, the notice contained several Chilling Effects URLs.

Each URL links to other DMCA notices on Chilling Effects, each sent by rival anti-piracy outfit Remove Your Media on behalf of Well Go USA Entertainment. They also target “Young Detective Dee”. This is an interesting situation that offers the potential for an endless loop, with the anti-piracy companies reporting each others’ “infringing” links on Chilling Effects in fresh notices, each time failing to get them removed.

The seeds of the “endless loop” phenomenon were also experienced by HBO for a while, with the anti-piracy company sending notices (such as this one) targeting dozens of Chilling Effects pages listing notices previously sent by the company.

While publishing notices is entirely legal, the potential for these loops really angers some notice senders.

On April 10 this year a Peter Walley sent a notice to Google complaining that his book was being made available on a “pirate site” without permission. Google removed the link in its indexes but, as is standard practice, linked to the notice on Chilling Effects. This enraged Walley.

None of these rantings had any effect, except to place yet another notice on Chilling Effects highlighting where the infringing material could be found.

It’s a lesson others should learn from too.