Addressing adblocking in your website ‘Terms of Use’ agreement

website terms no adblock

Most major websites today contain a “Terms of Use” page which defines?acceptable site-usage by visitors. These legally binding?agreements?cover a broad range of issues including acknowledgement of copyright laws, codes of user conduct, use?of sponsored content, and many other issues. But the issue of adblocking is seldom discussed.

Why do so few?websites address adblocking in their basic terms and conditions?

After looking at the Terms of Use?of around 40?different websites, I have not seen a single clause that looks anything?like these:

1. Visitor acknowledges the website derives income from advertising revenue, and consents to view advertising in exchange for use of website.

2. Visitor agrees that use of an adblocker is outside of acceptable use as defined by these terms and conditions.

Why not?

Given the massive financial losses caused by adblocking, the slow adoption of legal terms surrounding adblocking is surprising.

How do website Terms of Use work?

Typically, website terms?are “agreed to” either by one of two approaches:

  1. A?”Click Wrap” approach requires visitors to click an “I Agree” button after reading the terms.
  2. A “Browse Wrap“?approach simply states something along the lines of,?”continued usage of the website constitutes agreement with the terms and conditions”.

While the enforceability of either approach?has long been debated, US courts have upheld?the principle of website Terms of Use.

The first legal case involving a website’s Terms of Use?was the well publicized case of Hotmail vs. Van Money Pie. In this case, Microsoft sued a webmail user on the grounds that the website terms and conditions forbade users?from sending spam with webmail accounts. ?The courts upheld that the defendant was indeed bound by the terms and conditions, simply as a result of clicking “I agree” upon registration.

Since then, multiple additional court decisions have supported the enforceability of click-wrap agreements.

But that’s?not to say that all website terms and conditions are legally enforceable. Some aren’t.

When are website Terms of Use unenforceable?

What if you were never?forced to click “I agree”?

How binding are ‘browse wrap’ agreements?which users are unlikely to even see?

What if the terms and conditions are buried?in a link, deep in the page-footer?

Online footwear retailer, Zappo’s learned the answer to those questions the hard way. When facing dozens of lawsuits over a security breach, Zappo’s insisted that its “Terms of Use” required arbitration for legal disputes.

Zappo’s users disagreed on the grounds that they had never seen said terms, which were buried deep in the page footer:?(See if you can find the link below).


Zappos Terms of Use Footer


Zappo’s lost the case on the grounds that “No reasonable user would have grounds to click on the Terms”:

we cannot conclude that Plaintiffs ever viewed, let alone manifested assent to, the Terms of Use. The Terms of Use is inconspicuous, buried in the middle to bottom of every webpage among many other links, and the website never directs a user to the Terms of Use. No reasonable user would have reason to click on the Terms of Use, even those users who have alleged that they clicked and relied on statements found in adjacent links, such as the site?s ?Privacy Policy.?

The court followed with a more general comment on the fundamental requirements of contracts:?(emphasis ours)

The arbitration provision found in the Terms of Use purportedly binds all users of the website by virtue of their browsing. However, the advent of the Internet has not changed the basic requirements of a contract, and there is no agreement where there is no acceptance, no meeting of the minds, and no manifestation of assent. A party cannot assent to terms of which it has no knowledge or constructive notice, and a highly inconspicuous hyperlink buried among a sea of links does not provide such notice. Because Plaintiffs did not assent to the terms, no contract exists, and they cannot be compelled to arbitrate.

So what’s required for a binding website Terms of Use agreement?

The legal enforceability of website Terms of Use?is something of a grey area in contract law, but there are several factors which have been agreed upon by the courts.

Attorneys Shawn Organ and Matthew Corcoran of Jones Day penned the following set of guidelines for enforceable Terms of Use in The Privacy Data & Security Law Journal?

Generally, if four requirements are met, a Browse Wrap Agreement should be enforceable.

The requirements are:

1. Adequate notice of the existence of the proposed terms;

2. Meaningful opportunity to review the terms;

3. Adequate notice that taking a specified action manifests assent to the terms; and

4. Action specified in such notice is taken by the user.


Oliver Herzfeld, writing in Forbes, offers the following additional advice:

1. Provide clear and conspicuous notice of all terms;

2. Require counterparties to scroll through to the bottom of the terms and then type in their name in a signature box, click an ?I Agree? button or otherwise expressly and? actively manifest their assent to the terms;

3. Prohibit any use of the website or commencement of the relevant services prior to such express and active manifestation of assent; and

4. Periodically have counterparties reconfirm their agreement to the terms.

So you want to?add adblocking clauses to your Terms of Use agreement?

Website Terms of Use can easily be adapted to contain adblocking?clauses, or clauses that prohibit intentionally concealing elements of the page for purposes of hiding ads.

The question is enforceability. And to date (at least to the best of my knowledge), this has never come to court.

Could it be enforced in a court of law?

We already know that for website terms of use to be enforceable a website?should?first provide users with the opportunity of agreeing to the terms — and should?prevent use prior to agreement. Active consent is more likely to be enforceable than simple “browse wrap” agreements. And periodic reminders, which remind users that they are bound to the terms should also be automated sitewide.

Would that be enough to be enforceable? That’s for a judge to decide.

Certainly, technological measures like BlockAdblock should be the first line of defense against adblockers, but well publicized legal terms?may provide an additional layer of defense.


  • S Moynihen

    Ooooo.. that’ll stop me. A nasty warning from your lawyers. I hope your entire team dies in a fire. I don’t want ads. Period. It’s my machine. It’s my web browser. You have no right to block me.

    • The operator of a web server, like any other private sector business, reserves the right to refuse service to anyone. (Public sector websites are typically funded with tax revenue, not ads.)


        Oooooo… sure THATS gonna get me to disable adblocker right let me give you a internet lesson… In ThIs WoRlD iTs BlOcK oR bE bLoCkEd

  • Web Neumann

    And what happens when an Adblock plugin blocks the Terms of Use agreement? There are now adblockers that block modal popup windows and prevent the Terms of Use agreements from appearing at all.

    Users who have the adblockers installed never even know that they’re violating the ToS because the ToS never appeared for them.

    This is a mess.

  • Shame!

    Like I pay any attention to what you say in your Terms of Use. What are you going to do sue me?

    • Sue you, the same way record labels have sued P2P infringers, and then garnish your wages to collect a judgment against you.

      • Lunorian

        Do you think it’s scalable. What happens when 99% of internet users are using Adblock. No website can possibly keep up with the volume of cases needed to enforce this. No court district could either. It’d be too many cases.

  • SvSlazer18


    How pathetic. I can use this site and bypass all scripts with four lines of code…

  • Are these the same Terms of Use that disclaim all liability for damage that malware distributed through the advertising network used by the site does to the operating system installed on the end user’s PC?

    • Sarah G

      So, you want to blame other people for your shitty operating system? Why are you using Windows? And ya know, computer viruses can spread. Should other people be able to sue you because you use Windows? I’m just wondering if you should also be to blame if websites are to blame.

      • My laptop runs the Xubuntu distribution of GNU/Linux. What made you think I used Windows?

      • Wes Hanney

        Nice. Victim blaming. I wonder where we hear that often.

        • MattyB5

          Because let me guess, it’s never your fault?

  • Raj Meheni

    This is a great point, but not because users are going to pay any attention to it. Most users will probably ignore it. But if you add ad-blocking clauses to your terms of use, then ad-blocking plugins will then be in violation. That’s an important first step.

    • Then ad blockers will default to “plausible deniability” filter lists that perform only tracking blocking (e.g. Disconnect), non-free script blocking (e.g. LibreJS), bandwidth hog blocking (video ads on text articles), and malware blocking (most JS-driven ad networks have let through dangerous scripts and continue to do so). This allows ads, provided they are lightweight ads served using scripts released under a free software license and without tracking each user from site to site.

  • TooMuchJoyForJustOneBoy

    Mmm. This is a good point if the goal is to hold the adblockers accountable for violating your Terms. But it’s not really going to do much with individual users. You can’t really sue people for this so what’s the point? If you’re going to sue Adblock or Ublock, ok then maybe there’s something here. Otherwise it’s probably a waste of time.

  • As long as they spread out advertising via HTTPS or install malware without a real permission by users we will block with keweonDNS EVERY advertising. Even on Radio or TV Streams. For us and our users advertising is a security risk.

    Would be the same if they try to force you to disable your virus scanner to install the malware on your PC.

  • Lunorian

    Oh noes I’ll have to find an alternative to the sites with shitty made for Adsense content ???

  • Jacob Varkey

    I agree all the terms and conditions

  • Jacob Varkey

    Joined already the discussion and I agreed