Ad blockers, once regarded as a niche tool for web browsers, have evolved into a focal point of a significant conflict between internet users seeking relief from disruptive ads and publishers striving to sustain their business models. This clash has taken a critical turn as Germany’s highest court prepares to weigh in.
Germany’s Federal Supreme Court (BGH) has reopened a pivotal case that could lead to a nationwide ban on ad blockers. This legal dispute involves media giant Axel Springer and Eyeo, the Cologne-based company behind Adblock Plus, one of the most widely used ad-blocking solutions globally.
The Legal Battle Unfolds
Axel Springer, which owns influential outlets like Bild and Welt, contends that websites encompass more than just text and images; they are also composed of code that qualifies as protected computer programs. The company argues that when an ad blocker conceals an advertisement, it unlawfully interferes with the code that constitutes a website within a browser. Conversely, Eyeo asserts that it merely empowers users to choose what content they wish to view.
Initially, a lower court in Hamburg dismissed this argument. However, on July 31, 2025, the BGH overturned portions of that ruling, indicating that judges had not adequately assessed whether browser code, such as the Document Object Model (DOM) and CSS Object Model (CSSOM), is legally protected. They also questioned if hiding ads constitutes unauthorized interference.
“It cannot be excluded that the bytecode, or the code generated from it, is protected as a computer program, and that the ad blocker, through modification or modifying reproduction, infringed the exclusive right thereto,” stated the BGH (automated translation).
This case is now directed back to the Hamburg lower courts for more thorough technical examination.
Why This Case Matters
The ramifications of this case extend well beyond advertising. If the courts align with Springer’s perspective, it could classify any browser extension that alters website functionality—from privacy filters to accessibility enhancements—as illegal. This could adversely affect not only ad blockers but also tools that bolster accessibility, bolster security, or prevent online tracking.
Mozilla, the creator of Firefox, has raised alarms that Germany could become the first democratic nation to outlaw ad blockers, a move they argue would jeopardize user freedom, innovation, and online privacy.
In a statement, Daniel Nazer, Mozilla’s Senior IP & Product Counsel, highlighted that the ruling risks creating a “chilling effect,” potentially resulting in browsers restricting features and extension developers retreating to avoid legal repercussions.
“We sincerely hope that Germany does not follow in the footsteps of China as the second jurisdiction to ban ad blockers. Such a decision would significantly undermine users’ control over their online experiences and could set a precedent for similar restrictions elsewhere. This could embolden legal challenges against other extensions that protect privacy, enhance accessibility, or improve security,” added Nazer.
What Lies Ahead
The legal proceedings are far from concluded, as the case now returns to Hamburg’s lower courts, where additional hearings may continue for years. For now, ad blockers remain legal in Germany, but their future hangs in the balance.
