Germany’s top court just cracked open a case that could make ad blockers illegal by redefining what a browser does. Axel Springer’s claim? That Adblock Plus “intervenes in the in-memory execution structures (DOM, CSSOM, rendering tree), this constituting unlawful reproduction and modification.” https://www.bleepingcomputer.com/news/legal/mozilla-warns-germany-could-soon-declare-ad-blockers-illegal/
Mozilla warns the fallout wouldn’t stop with ads. Daniel Nazer points out it could sweep up “extensions used to improve accessibility, to evaluate accessibility, or to protect privacy.” https://blog.mozilla.org/netpolicy/2025/08/14/is-germany-on-the-brink-of-banning-ad-blockers-user-freedom-privacy-and-security-is-at-risk/
PCWorld confirms the case is back in motion, with the Federal Court of Justice hunting for “legal clarification” that could drag on for two years. https://www.pcworld.com/article/2882192/a-reopened-lawsuit-might-make-ad-blockers-illegal-in-germany.html TechRadar says the worst-case scenario is a full national ban. https://www.techradar.com/vpn/vpn-privacy-security/germanys-possible-ad-blocker-ban-could-threaten-user-freedom-and-privacy-says-mozilla
The real fight isn’t over users. It’s over Eyeo’s “acceptable ads” model—blocking some ads while swapping in paid ones. But by framing DOM manipulation as copyright violation, the lawsuit risks criminalizing normal browser behavior.
If this logic holds, accessibility tools, screen readers, even privacy filters could be next. That’s not ad tech. That’s user agency on trial.