A German court's recent decision on copyright is "a first glimpse at the devastating consequences an earlier ruling by the European Court of Justice may have on the future of the Internet," Pirate Party MEP Julia Reda has told Ars.

In the latest case, a Hamburg court ruled that the operator of a website violated on copyright by publishing a link to material that was infringing, even though the site operator was unaware of this fact. As Ars reported in September, an earlier judgment from the Court of Justice of the European Union (CJEU) held that posting hyperlinks to pirated copies of material isn't illegal provided it is done without knowledge that they are unauthorised versions, and it is not carried out for financial gain.

The CJEU had said that "when the posting of hyperlinks is carried out for profit, it can be expected that the person who posted such a link carries out the necessary checks to ensure that the work concerned is not illegally published on the website to which those hyperlinks lead." But it did not specify what constituted "carried out for profit."

Reda explained to Ars how, in her view, the German ruling had gone beyond the CJEU, and why it's a problem: "The Hamburg court took a very drastic interpretation of this already problematic ruling and decided that even if a link does not serve a commercial purpose in itself, but is posted on a commercial website, the linking party is liable for a copyright infringement on the website it links to."

The MEP argues that the much broader interpretation could have a serious impact on the Internet in the 28-member-state bloc: "If this rule is going to be enforced across the board, it will have a dramatic chilling effect on online communication, because even a duty to contact a website owner before setting a link would create an enormous administrative burden due to the very large number of links set every minute."

Jim Killock, executive director of the Open Rights Group, agreed. In an e-mail to Ars, he said: "If this was to become standard practice then it would make a lot of what publishers do today extremely risky as they would need to know the licensing status of everything they linked to."

The German case was unusual in that it concerned a link to a photograph originally released under a Creative Commons (CC) licence, thereby making it freely available subject to certain conditions. On the site where the copy in question was stored, the terms of the CC licence were not observed properly, which meant that it constituted a copyright infringement. The website owner that linked to that copy was unaware of this fact, and did not check that the CC licence had been followed.

The Hamburg court ruled that even though the link in question was not used to generate revenue directly, the site as a whole was commercial, since it sells learning materials via one of its Web pages. In the German court's interpretation, this meant that it was "carried on for profit," and that the link to infringing material was itself violating copyright, in light of the CJEU's guidance.

Killock told Ars: "While this doesn’t have a direct impact in the UK, and is open to challenge in Germany, it shows the tendency for copyright enforcement to tighten over time." Moreover, British and other national courts in the EU may look to this decision when similar copyright cases appear before them.

Andrew Katz, partner at Moorcrofts LLP, pointed out in an e-mail to Ars another problem that is likely to arise from this new approach:

It’s always been assumed that liability for infringement itself is strict [that is, regardless of culpability], but to retain strict liability and extend it to linking is likely to result in some very unreasonable consequences, not least that the content of the site linked to may change over time, or that something may not be infringing initially, but may become infringing because of an act of the proprietor of the linked site (or just because a licence—for example a time-limited licence to use an image—may expire).

But reversing the new principle would be hard, Reda told Ars: "establishing that links do not constitute copyright infringement would most likely require a redefinition of the notion of communication to the public, the underlying copyright-relevant act enshrined in the [EU's] 2001 InfoSoc directive. Rights holders are generally very reluctant to redefining the scope of these exclusive rights, so their resistance to such an endeavour can be expected."

Ars asked the Federation Against Copyright Theft (FACT) whether it expects to use the new ruling to combat links to unauthorised material, but it hadn't got back to us at time of publication.