Is Adblock Plus violating the DMCA?

As just about everyone knows,?Digital Millennium Copyright Act or DMCA is a United States copyright law that applies to all copyrighted digital media. ?While originally penned to?curb the illegal copying and distribution of digital media — there’s a good chance the DMCA applies in part to some practices of Adblock Plus and other adblockers.



Big fat IANAL disclaimer:?Before we dig in, let me state for the record that I am not a lawyer or legal expert. ?But having founded?3 companies and exited?two, I’ve had many years of professional experience with copyright issues, trademark cases and even WIPO actions. ?My personal experience with copyright lawyers is that?if you ask?ten?of them for their opinion on any given topic — you’re probably going to get?ten completely different answers. In my experience, this?tends to be a?topic with a whole lot of ‘wiggle room’. So to anyone reading this post hoping for answers, you’re not going to find any here.?My goal is?just to ask questions.

With that having been said, let’s start thinking in this direction. ?Hopefully somebody far smarter than I am will take the ball from here.


Circumvention of Access Controls

One of the key sets of provisions?in the DMCA deals with?the?”circumvention of access controls“. ?These “access control” provisions forbid bypassing any technological measures designed to prevent or limit access to a work.


Here’s a very clear explanation of exactly what this?means from Stoel Rives?–?whose legal experts?are far better versed in the DMCA?than I’ll ever be: ?(Emphasis mine)

The DMCA’s basic rule prohibits the act of circumventing technological measures that “effectively control access” to a copyrighted work without the consent of the copyright owner. (An “effective access control” is a measure that in the ordinary course of its operation requires the application of information, or a process or treatment, with the authority of the copyright owner, to gain access to the work.) Prohibited acts therefore include descrambling a scrambled work, decrypting an encrypted work, or otherwise avoiding, bypassing, removing, deactivating or impairing a technological measure without the authority of the copyright owner.

To be clear: The “circumvention of access controls” provisions do not exist solely in the context of?copying or distributing media. ?They reference the ‘accessing’?of media which?has been specifically access-restricted by technological means. Such technological means typically?include?DRM, encryption, password-protection and other methods for restricting access to a work.

So how might?this apply to ad blocking? ?(You probably see where I’m going with this.)

Thousands of websites have installed BlockAdblock?and other restrictive?measures designed to limit website access such?that only those visitors?not using an adblocker are permitted to view the content. ?BlockAdblock and other anti-adblock systems are by nature?”technological measures that effectively control access to a work”, to use the wording?from the DMCA.

So?what happens when Adblock Plus develops new technologies purposefully designed (more on this later) to circumvent such access controls?

I’m no legal scholar, but the Circumvention of Access Controls provisions of the DMCA would?certainly?appear to apply.

But wait. There’s more.

The DMCA doesn’t just stop there.? It also specifically bans tools that enable users to circumvent access controls.

Products that “aid and abet” circumvention

Again, the legal experts at Stoel Rives say it better than I ever could: (Emphasis mine)

The DMCA’s ban on circumventing access control measures is supplemented by its prohibition on trafficking in certain products and services that in effect “aid and abet” those who would “break and enter”, i.e., circumvent access control measures.


The exact text of the DMCA is as follows:?(Emphasis mine)

No person shall manufacture, import, offer to the public, provide, or otherwise traffic in any technology, product, service, device, component, or part thereof, that?

[a] is primarily designed or produced for the purpose of circumventing a technological measure that effectively controls access to a work protected under this title;
[b] has only limited commercially significant purpose or use other than to circumvent a technological measure that effectively controls access to a work protected under this title; or
[c] is marketed by that person or another acting in concert with that person with that person?s knowledge for use in circumventing a technological measure that effectively controls access to a work protected under this title.


Again, that sure looks like it applies.

But there’s an issue with Adblock Plus that makes this question of whether Adblock Plus violates the DMCA more nuanced than it might appear at first: ?What we commonly think of as “Adblock Plus” is actually two different beasts. ?Adblock Plus requires a “filter list” to actually block ads. ?If you’re an Adblock Plus user, the chances are you’re using “EasyList” which is (by far) the most popular filter list in the world. ? EasyList contains tens of thousands “rules” which tell Adblock Plus what to block and what not to block. ?Without EasyList or another filter list, Adblock Plus can’t do much of anything at all.

EasyList is billed as a separate entity from Adblock Plus. ?The list is released free under a Creative Commons license and the GPL, which means other competing ad-blockers can (and do) freely incorporate the list into their systems as well. And as an Adblock Plus user, you’re free to use a different list other than EasyList. While other lists are?available from other sources, the percentage of Adblock Plus users using EasyList is very?close to 100%.

Still, an important legal question must be asked:? Who?exactly?doing the circumvention? ?Is Adblock Plus doing the dirty work? Or is it?EasyList?


Does?Adblock Plus circumvent access controls? ?Or is it?EasyList?

I’ve previously covered the rather flimsy separation of Adblock Plus and?EasyList in a previous post, but?just to re-cap quickly: ?Adblock Plus claims on their site that AdBlock Plus itself “has no functionality”. (Never mind the overt absurdity of this statement for a moment). ?They?claim the real work is done by filter lists, which as already stated, are separate entities?from Adblock Plus.

Screen Shot 2016-02-29 at 1.21.43 PM

Screenshot from the Adblock Plus website


If you read that carefully, you’ll probably note that while Adblock Plus and EasyList are separate entities, they’re pretty much delivered at the same time, and as part of the same installation process. In other words, “We?don’t actually block?anything. But we’ll just go ahead and enable by default the largest and most popular filter list in the world, which will block ads on almost every website you visit.'”. ??This seems to my eye like a rather obvious effort to conceptually (and legally) distinguish the Adblock Plus software from the EasyList filters, while essentially bundling them for all intents and purposes.



There’s much more to say about the relationship of Adblock Plus and EasyList but here are a few quick points:

  • EasyList is directly hosted on the Adblock Plus website (
  • Users are directed to EasyList by Adblock Plus immediately following installation.
  • Easylist is enabled by default.
  • Wladimir Palant who developed Adblock Plus also developed the EasyList site.

I could go on, but we’ll leave further examination of this relationship?for?another post. ?In my personal view (and most probably everyone else’s) the two entities are two sides of the same coin despite the GPL status of EasyList.?Asking which entity is ultimately doing the actual access-control?circumvention?seems a bit like asking whether it’s guns or bullets that actually hurt people.


Adblock Plus and Circumvention of Access Controls

Ultimately,?the?legal distinction between Adblock Plus and its EasyList?may not matter anyway: While EasyList does of course?define the specific site elements to be filtered on any given domain, it is Adblock Plus by their own admission (I’ll get to this below) which designs?their?product with the intent to circumvent access controls.?

Take this November 2015?blog post from the official Adblock Plus?website for example:? Here, Adblock Plus developer (and Eyeo employee)?Dave Barker describes?a new?Adblock Plus feature which will allow filter-list writers to circumvent anti-Adblock technologies.


click for full screenshot


Again, that’s an Adblock Plus software developer — not a filter-list author — publicly discussing new features specifically designed to circumvent Adblock detection technologies which would normally restrict access to a website. ?I’m just a legal layman, but it seems cut and dry from where I’m standing: This is?product feature specifically designed to “aid and abet” the circumvention of access controls. Again, the DMCA’s anti-circumvention measures would certainly seem to apply.


EasyList: “…primarily designed or produced for the purpose of circumventing?a techological measure”

Of course, EasyList is also very clearly involved in disabling and circumventing access controls. There is even a list called “Anti Adblock Filters“, whose eponymous?intent is circumvention. ?The list authors ask for user support by writing “Please report any unblocked obtrusive anti-adblock messages or problems”. ?In other words: ?“If you experience any problems circumventing access controls, please just give us a shout.” ?

On EasyList’s “An Anti-Adblock Guide for Site Admins“, which as you might have guessed is a guide for site admins to bypass anti-adblock measures, EasyList clarifies their policy about circumvention:

Our policy states the following about those so-called anti-adblock measurements: “Anti-Adblock should only be challenged if the system limits website functionality or causes significant disruption to browsing”.

Got that? In other words ?”Our?access circumvention?measures should only be employed in cases where?the system restricts access.” ?Glad that’s cleared up.

And as for?EasyList being?a Creative Commons / GPL project:?EasyList’s third-party status as a Creative Commons?work does not appear to afford it any special protections under the DMCA. ?For one, regardless of EasyList’s?”Anti Adblock Filters” public license it is still a manufactured “product, service, component or part” primarily?designed?to circumvent access controls?–?and clearly it is “offered to the public”. ?Again, the DMCA would clearly appear to apply.

Lastly,?the Anti Adblock Filters list?(whose stated purpose is anti-circumvention) ?is very clearly trafficked by Eyeo, who serves?the EasyList site?as a subdomain of


Mounting a?more effective legal challenge

Multiple major publications from to Forbes now block Adblock — some more successfully than others. ? German content creators?like Zeitt Online, Handelsblatt?and Axel Springer?have attempted to mount legal challenges against Eyeo and?Adblock Plus with regard to their core function of blocking ads. ?These attempts failed in court. ?A?more interesting (and possibly far more productive) strategic avenue for US publishers however, might?be to challenge Adblock Plus’s intentional?circumvention of publishers’?access controls under the DMCA.

To my eyes, the DMCA?certainly seems to apply.

Of course,?IANAL.

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  • Christopher Koch

    BlockAdBlock does about as much to “restrict access” as WinRAR does. I could still block ads using the operating system’s “hosts” file or just “View page source” in my web browser because the content was still delivered. Any “access restriction” you do is only superficial.

  • smek2

    No it doesn’t. And every site that nags or outright blocks me for using
    Adblock Plus (including your little site and script) is quickly ignored
    and forgotten thereafter.
    I’m not even joking. Want to know how i even found your site to begin with? By being nagged by your script on some shady low level wanna-be Youtube website that i never even heard of before (and landed on by accident and never will return to again).
    By the way, that site, the one that used your “technology” and even going as far as publicy showing your logo and link to your website (while blocking users for using AdBlock), had tons of DMCA violating material to offer, making this especially ironic.
    And now i will move on, quickly forgetting the both of you.

  • You script was killed and to paraphrase an early internet meme, “All your Content are Belong to Us”. Thanks for helping me test my latest acquisition.

  • PilleniusMC

    Funny but not working properly. I needed one minute to disable blockadblock, so work on it that I need five or more minutes.

  • Telyn

    As far as I am aware, it doesn’t really make a blind bit of difference as the DMCA is unenforceable outside the US, as long as all their servers are run and hosted by non-US companies.

    • FF222

      Most jurisdictions have anti-circumvention laws in place that are very similar to the DMCA, and prohibit the circumvention of access control mechanisms. So, even though not because of the DMCA, but because of the appropriate local law, but circumvention of anti ad blockers is just as illegal in almost all over the world, as it is in the US.

    • Monar Davesh

      Fair point… but the biggest advertising companies in the world are in the USA. Google, Facebook, etc.

  • Adam

    Kind of hard to believe adblocking is illegal when pretty much every single time this issue has been raised in court, the court rules in favor of the adblocker 🙂

    • Pletherona

      Kind of hard to believe you just read that entire article and completely missed the point.

      1) We’re not talking about Europe here. The DMCA is a US law. It’s never come to trial in the USA.
      2) Even in Europe, the trials have focused on “ad blocking” not on “circumvention” which is the topic of this article. It is very much up in the air whether a suit on this matter would be won by adblockers in Europe.

      • Adam

        The article is bullshit. The circumvention clause cited is supposed to apply to “technological measures that effectively controls access to a work”.
        Last I checked, ads don’t control access to anything, they just irritate you and slow page loading times. Anti-adblock-blocking (lol) is different, but adblocking itself certainly is fine.

        Next you’ll be saying we’re not allowed to change the channel or turn off our TV when adverts come on.

        I genuinely don’t understand where people get the idea that you have the right to mandate people to view your ads, because it’s pretty silly. People have every right to choose how they access content (and ads don’t impact the actual content itself), and if they didn’t then it WOULD have been raised in trial by now. The billions of dollars lost in ad revenue thanks to good ol’ Adblock, should have seen this happen years ago. But it hasn’t. Why is that?

        • Hjulle

          I’d argue that blockadblock is an access control technology. Its purpose is to disallows access to the site for users that blocks their ads.

          And the point of the article is that the anti-anti-adblocking technology built into ABP may be violating DMCA, not the adblocking.

          • sdf

            Yeah, even though I personally feel any idiots who use javascript to handle access control deserve to be hacked (oh wait, that is ACTUALLY becoming quite popular); it basically is hacking on a small level.

          • Scott Fulkerson

            The problem is that blockadblock doesn’t protect anything in any real meaningful way, because it is easily circumvented by disallowing scripts- which is something that the browser is entitled to do arbitrarily due to security issues.

        • Monar Davesh

          Look up. Swoooooosh.

          That’s the point of the article going over your head.

        • Upton Measures

          Jesus there are some stupid people here. They’re talking about adblockers and anti-Adblock measures. Yeah of course ads don’t control access to a work. Lolwut?

      • Scott Fulkerson

        it hasn’t been rasied in the U.S. courts because the U.S. courts would invariably rule against the anti-adblocker per curriam on summary judgment because of the fact that ads and ad blocking have to do with access to the server, and have nothing to do with access to the work in any significant meaningful way within the scope of the intent of copyright law. This argument is essentially a thinly-veilled and weak attempt to game the law that our courts don’t allow.

        To the contrary serving ads actually dilutes the copyright to a work, since a third party (the person whom runs the ad) is making a profit which is directly proximate of the allegedly protected work, where that third party does not own the copyright or a valid license thereof.

    • Monar Davesh

      Really? How many times has it come to trial in the USA under the DMCA … which … appears … to… be … the … entire … point … of … this … post

      • Adam

        Why hasn’t it come to trial under the DMCA? Ever think of that?

        • Monar Davesh

          So because it hasn’t happened it’s not going to happen.

          By the same logic, you’re going to live forever.

      • Chilly8

        Adblock is based in Germany, so they only have to obey German law, and the courts over there have said that AdBlock is legal.

        A company in Germany is not subject to the laws of the United States.

  • Chilly8

    That only applies if you do it for commercial or financial gain, so using it in your own home for your own private use, is not a crime.

    • SvSlazer18

      Stop deleting my comments you pussies. Here are a list of filters that bypass their egoish bullshit:


      I’ll spam this everywhere. Let’s see for how long you can keep your business up.

    • AhsanEjaz

      Nope, DMCA is not restricted to that. It includes any case not only commercial.

      • Chilly8

        It has to be for the purpose of commercial or private financial gain, So using your home firewall to block anti-adblock scripts is a criminal act, since you are not doing it for any financial gain.

        • AhsanEjaz

          Financial gain or not does not matter. Please bother to read the law.

          • Chilly8

            Section 1201 does have a “commercial or financial private gain” requirement, so doing it at home, with your personal firewall, for personal, non-commercial use, does not break the alw.

          • AhsanEjaz
  • SvSlazer18

    Stop deleting my comments you pussies. Here are a list of filters that bypass their egoish bullshit:


    I’ll spam this everywhere. Let’s see for how long you can keep your business up.

  • you suck guys, i’ll develop a block blockadblock extension

  • eniveld

    Thanks for the fascinating article. I’m just coming up to speed on this particular issue. Since it’s a year and a half since you originally wrote this, I’m wondering if you have any updates you’d care to share on how the DMCA has been applied to stop ad blockers since you wrote this?

    From my perspective, a key legal precedent was set when a U.S. District Court denied Fox Broadcasting Co’s copyright claims against Dish Network, as described here:,_LLC

    Tivo has ad skipping technology as well, which has survived court challenges:

    My guess is that ad blockers will continue to be allowed to offer ad blocking services without being shut down by our courts, and we’ll unfortunately be stuck with this cat and mouse game.

  • Antone Morane

    Congratulations! They have made more pirates, have a lucrative business with blockadblock, congratulations again! Jijijijijiji

  • Dahdahdit

    First of all. No, the DMCA does not apply, but lets pretend that the arguments put forth actually hold water. This would mean, by the same logic, that the access control technology used to limit the end user from accessing the content by detecting the anti adblock method is similarly in violation of the DMCA.

    Using an anti adblock script literally does the same thing a circumvention of the same script does.

  • Chilly8

    the EFF wrote an article saying DMCA 1201 cannot pass constitutional scrunity, but they are wrong.

    Normally, it would be unconstitutional, but the law came in as a result of a copyright treaty back in 1990s. Since the law implements a treaty, it have Congress license to piss on the Constitution when writing the DMCA

    International treaties do override the constitution. That is why more draconian copyright provisions have been written into proposed international agreements such as ACTA, TPP, and NAFTA 2.0.

    The copyright cartels are trying to get those in these agreements so that the laws they want, which normally be unconstitutional, can get passed.

  • I-Block-Ads

    That’s like saying customers who visit a store should be forced to buy something or they can be charged with committed a crime. and anyone who supports invading users privacy by collecting private information should be charged with theft.

    You are the one who is committing the crime not us…

  • PikaBot

    The content loads from the server whether adblock-blockers kick in or not. They do not constitute an access control. Your entire position collapses at the very first test, you ridiculous person.

  • itv cielo

    thank you very much for this service

  • Scott Fulkerson

    The problem with this theory is that DMCA, as a matter of federal law, cannot be construed in such a way to provide any additional copyright protections that the U.S. Copyright act didn’t already provide for before the DMCA statute was passed. (This is actually a required rule of construction in the DMCA itself and also has been expressed numerous in U.S. Case law in multiple federal circuits.)

    Therefore, simply put, DMCA cannot, as a requisite matter of law, be read in such a way as to prohibit ad blocking- because of the fact that ad blocking has nothing to do with restricting the access to or copying of a work (which is what DMCA was intended by congress to concern). This is because when dealing with ad blocking we are dealing with access to a domain name and a server, not access to the content itself, which could still be harvested by alternate programs that aren’t web browsers- thus making ad-blocking software and it’s anti-thesis constructively moot in terms of restricting access to the work itself in any real or meaningful way.