Ad Blocking

IAB Tech Lab Publisher Ad Blocking Primer

The IAB Tech Lab Publisher Ad Blocking Primer outlines the range of communications and response tactics available to publishers to connect with visitors who have downloaded ad blocking software. The goal is to give consumers a clear understanding of how ad blocking affects the free content value exchange. Consumers can then make an educated choice as to whether or not to turn off ad blocking to access free content or select another option. Read the press release.

The primer identifies DEAL (Detect, Explain, Ask, and Lift or Limit) as a recommended approach for publishers to connect with ad blocking consumers through a step-by-step process:

  • Detect ad blocking, in order to initiate a conversation
  • Explain the value exchange that advertising enables
  • Ask for changed behavior in order to maintain an equitable exchange
  • Lift restrictions or Limit access in response to consumer


What is Ad Blocking? Global Ad Blocking Studies Ad Blocking in the News Ad Blocking Statistics


LEAN_LogoThe IAB Tech Lab launched the LEAN Ads Program in late 2015. LEAN stands for Light, Encrypted, AdChoice-supported, Non-invasive ads. These are principles that will help guide the next phases of advertising technical standards for the global digital advertising supply chain.

L: Light. Limited file size with strict data call guidelines.
E: Encrypted. Assure user privacy with ads delivered over HTTPS. Protect server-to-server communication. 
A: Ad Choices Support. All ads should support DAA’s consumer privacy programs.
N: Non-invasive/Non-disruptive. Ads that supplement the user experience and don’t disrupt it. This includes covering content and sound enabled by default.

Alongside efforts to promote secure ad delivery and other consumer protections, the IAB Tech Lab is developing tighter guidelines on page load impact and file sizes in order to have a lighter set of ads.

  • The IAB Tech Lab cares about the user experience, which is a top priority in all our activities as we develop creative standards and platforms.
  • The IAB Tech Lab will issue guidance on lighter ad standards for advertising sales and ad operations, aligning with HTML5 and other IAB Ad Unit Guidelines.
  • Our new guidelines and standards, with the sunset of Flash in favor of HTML5 has started a path towards better optimization, security, and user experience.
  • As part of the standards work, the IAB Tech Lab focuses on the minimum amount of data calls required to achieve good user experience and targeting, reducing latency and making sure consumers are served the ads that were intended for them.
  • The IAB Tech Lab is investing in the creation of new, dynamic, and responsive ad units that will further make user experience better across screens.

Read Scott Cunningham’s blog post on Getting LEAN with Digital Ad UX

Detection & Post Detection

The IAB Tech Lab is developing open technology for publishers and other website content providers to consistently and reliably determine whether ad blocking is occurring on a page.

The IAB Tech Lab engineering team in collaboration with IAB members has been developing a detection utility as the ad blocking software is often not detectable by publishers’ normal analytics tools.

Most ad blockers operate in a manner that is intentionally resistant to detection.  While homegrown or vendor-created detection technologies can be used, their inconsistent discovery of ad blockers results in different measured blocking rates.  A centralized code base that determines whether ad blocking is present and is highly resistant will provide consistent measures.

  • Detection Script: The IAB Tech Lab is developing a detection script to consistently and reliably determine whether ad blocking is happening during a page load. This project is involving engineers and software developers from member companies.
  • Post Detection Best Practices: The IAB Tech Lab is preparing some guidance on what options are available to publishers once ad blocking is detected. It may include non-advertising options for businesses, such as paywalls, limiting available content, requiring accounts, etc.
  • The IAB Ad Blocking Working Group is addressing end users’ experiences and analyzing data about their tolerance to messaging, as well as developing best practices and principles for engaging consumers with ad blockers installed. The Working Group addresses detection from a technical standpoint and analyzes ad blocker behavior.

Want to discuss Ad Blocking? Contact us at

Better User Experience Solutions

The IAB Tech Lab is addressing concerns around user experience including the frictional contribution from latency and non-secured ad delivery (non HTTPS).

  • The path to viewable impressions and the market adoption of HTTPS/encryption of the supply chain greatly enhances user experience and protection of end users.
  • The IAB Tech Lab is preparing guidelines and best practices for site redesign and viewability to ensure that ad operations personnel contribute to a better user experience rather than a negative one.
  • Continued focus on development such as the Trustworthy Accountability Group (TAG) to counter the fear of malware from consumers and to create a safer experience for consumers
  • TAG’s Inventory Quality Guidelines (IQG) promotes transparency and trust in the marketplace and aims at reducing friction

Read Brendan Riordan-Butterworth’s blog post on Adopting Encryption: The Need for HTTPS

IAB Research

To ensure that we develop viable, long-term solutions, IAB has conducted research around ad blocking and user experience. IAB is also developing new research focusing on web browsers, consumer experience, data calls, latency, and other adverse effects of the supply chain on user experience so that we can make even better decisions about optimized standards and best practices for design, development, sales and operations teams.

New research will address:

  • Consumer attitudes and usage
  • The internet value proposition
  • Utility of advertising to consumers

Global Ad Blocking Studies

PwC OVK Ad Blocker Study – IAB Germany
New IAB UK research reveals latest ad blocking levels – IAB UK

Developed by the Ad Blocking Working Group

IAB Tech Lab Contact

Brendan Riordan-Butterworth
Director, Technical Standards