Press Release: Media Rating Council Updates Viewable Ad Impression Measurement Guidelines

Results of Reconciliation Studies Integrated into Version 2.0 to Reduce Discrepancies in Reporting


NEW YORK – Aug. 18, 2015 The Media Rating Council (MRC) announced that it has released Viewable Ad Impression Measurement Guidelines 2.0 to address specific issues identified since the original Guidelines were released on June 30, 2014. These issues were identified primarily through a series of reconciliation projects that were designed to pinpoint the causes for discrepancies in viewable impression counts among MRC-accredited vendors.

While this revision to the Guidelines includes several updates, the baseline standards for desktop Viewable Ad Impressions remain the same. A Viewable Impression can be counted as such if, and only if, at least 50 percent of the pixels are in view for a minimum of one continuous second for display and two continuous seconds for video advertisements.

“Viewable Impressions are the foundational element for ultimately defining an Audience Based Currency that will allow the industry to better measure digital ad efficacy and engagement,” said George W. Ivie, Executive Director and CEO, Media Rating Council. “Therefore, it’s critical that the Guidelines for measuring Viewable Impressions address those technical nuances, and the discrepancies they can cause, that the buy and sell side of the industry have encountered.”

Below is a summary of the key changes including in Version 2.0:

  • Mobile Viewable Impression Measurement (pp. 1, 13 in the updated Guidelines): Specifies that these Guidelines are intended for desktop advertising measurement, and that MRC has issued separate Interim Guidance specific to mobile viewability measurement. Also, notes that desktop viewable impression counts should be reported separately from mobile viewable impression counts.
  • Rendered Served Ad Impressions (p. 2): Definition of this term, and explanation for why the basis for served ad counts used in viewability-related metrics calculations (the Measured Rate, specifically) should exclude served ads counted using a “Count on Decision” methodology.
  • Measurement of Multi-Ad Units (p. 6): Specifies that ad units should be measured individually for viewability, regardless of whether and how they may be packaged together for monetization purposes.
  • Measurement when Multiple Measurement Tags Are Present (p. 6): Note on how some measurers choose to not measure certain ads for viewability that also may be tagged for measurement by another vendor, or are served by another ad server than the measurer. Disclosure of such situations is now a requirement.
  • Note on the Use of the Page Visibility API and the Flash-Based Throttle Indicator in Viewability Measurement Methods(pp. 6-7): Calls attention to two tools available to viewability measurers that can provide evidence concerning the viewability of an ad in certain situations. While neither tool is sufficient as a standalone solution, the leveraging of these tools, when available, is encouraged to be included as part of measurers’ viewability measurement methodologies.
  • Viewability Measurement when Other Ad Verification Functions are Also Performed (p. 13): Emphasizes the need for consistency in when the viewable impression count should occur when other Ad Verification functions (such as consideration of site contextual issues, geographic targeting, or other criteria) are also applied.
  • Viewable Impression Reporting when Sophisticated Invalid Traffic Detection Processes are Also Applied (p. 14): Refers to MRC’s Invalid Traffic Detection and Filtration Guidelines Addendum, Appendix A (currently in draft), for specific guidance on how reporting of viewable impressions should be addressed when enhanced levels of invalid traffic filtration (referred to as “Sophisticated Invalid Traffic” filtration) are applied by the measurer. Examples of Sophisticated Invalid Traffic include traffic originating from hijacked devices, malware or misappropriated content.

These guidelines are effective immediately. Current MRC-accredited viewability measurers must be fully compliant with the updated guidelines within 60 days.

MRC expects the digital advertising marketplace to continue its move toward adopting Viewable Impressions. As noted previously, MRC is conducting due diligence around mobile viewable impression measurements and expects to issue a draft version of these guidelines for public comment by the end of calendar year 2015.

To date, MRC has achieved the following milestone efforts to standardize digital measurement:

  • June 2011 – Viewability formally established as a 3MS (Making Measurement Make Sense) priority
  • Summer 2012 Spring 2014 – MRC conducted Viewable Impressions agency pilot; advised industry against trading on viewability; conducted audits of measurers and methods; worked with industry groups to develop standards for viewability measurement
  • March 2014 – MRC announced lift of advisory for transacting on viewable impressions (effective immediately for display advertising, lifted on June 30 for video ads);
  • June 2014 – MRC formally issued Viewable Ad Impression Measurement Guidelines, which codified parameters for measuring viewable impressions for both display and video ads; included new provisions designed to reduce discrepant results among different viewability measurers
  • October 2014 – MRC issued Viewability Implementation Guidance document aimed at reducing marketplace confusion and enumerated certain best practices related to the transition to trading on viewability
  • Spring/Summer 2015 – MRC oversaw two more rounds of viewability vendor reconciliation research; learnings included inViewable Ad Impression Measurement Guidelines 2.0

Please visit, or the Making Measurement Make Sense website,, for more information. To view the updated guidelines, please visit:


About the Media Rating Council (MRC)

The MRC is a non-profit industry association established in 1963 composed of leading television, radio, print and Internet companies, as well as advertisers, advertising agencies and trade associations whose goal is to ensure measurement services that are valid, reliable and effective.  Measurement services desiring MRC Accreditation are required to disclose to their customers all methodological aspects of their service; comply with the MRC Minimum Standards for Media Rating Research and other standards MRC produces; and submit to MRC-designed audits to authenticate and illuminate their procedures.  In addition, the MRC membership actively pursues research issues they consider priorities in an effort to improve the quality of research in the marketplace.  Currently approximately 100 research products are audited by the MRC.