According to reports on August 19， a recent ruling by the German Federal Court of Justice (BGH) has reignited legal debates surrounding whether browser ad-blocking plugins infringe upon copyright.
The case was initiated by online media company Axel Springer against Eyeo， the manufacturer of the popular Adblock Plus browser plugin. Axel Springer contended that ad blockers threatened its revenue and asserted that the plugin’s operation within the browser constituted copyright infringement.
This claim was predicated on the argument that a website’s HTML/CSS constitutes a protected computer program. Ad-blocking plugins， by interfering with the in-memory execution structures (DOM， CSSOM， render tree)， were argued to be engaging in unlawful reproduction and modification.
Initially， this assertion was dismissed by a lower court in Hamburg. However， the BGH’s new decision found the earlier dismissal to be flawed， overturning parts of the appeal and remanding the case for further review.
Daniel Nazer， a Senior Intellectual Property and Product Advisor at Mozilla， commented that due to the technical nature of the legal dispute， an injunction could potentially affect other browser extensions and limit user choices.
Nazer elaborated that users may wish for their browsers or browser extensions to modify webpages for various reasons， including enhancing accessibility， protecting privacy， and more. The ability to customize the browsing experience is a key aspect of user empowerment online.
Under the BGH’s ruling， Springer’s arguments will be re-evaluated to determine whether DOM， CSS， and bytecode are indeed considered protected computer programs and if the modifications made by ad blockers are lawful. This legal examination delves into the fundamental nature of web content and the tools users employ to manage it.
While ad-blocking plugins are not currently deemed illegal， Springer’s case has now commenced retrial. Mozilla notes that it could take several years to reach a definitive conclusion. This prolonged legal process underscores the complexity of balancing copyright law with user agency and the evolving digital landscape.
In the interim， this situation could potentially create a chilling effect on browser and plugin developers. Developers might feel compelled to limit the functionality of their tools to circumvent potential legal risks， thereby stifling innovation and user customization options.
