Viewability: Let’s End The Numbers Game

ericboscorevisedData-Driven Thinking” is written by members of the media community and contains fresh ideas on the digital revolution in media.

Today’s column is written by Eric Bosco, CEO at ChoiceStream.


It’s a phrase tossed back and forth in sales meetings, delivered solemnly by speakers pacing conference stages and increasingly mandated by brands in their agency and vendor contracts. This metric has gone viral, taking a front seat in many digital advertising campaigns.

But its wildfire-like spread has caused many clients who demand it to overlook what it truly means beneath the surface. The actual measurement remains unstandardized and nascent. It is far from perfect. Yet many are so concerned with guaranteeing viewable impressions when something concrete, like conversion rates, may be suffering.

Viewability is still in its awkward teenage stage. It’s only been a year since the Media Rating Council (MRC) defined and passed guidance for display ads, and just six months since the IAB recommended 70% as a threshold for buyers and sellers. Experts are still evolving their opinions on what percentage of viewable impressions advertisers should shoot for and, more importantly, we still lack a uniform method of measurement.

The year 2015 should been deemed a “year of transition,” and there is a certainly much change ahead as far as viewability and its corresponding metrics go.

Large Discrepancies

Due to differences in measurement, I’ve seen discrepancies as high as 50% between third-party vendors for the same campaign. While 50% variance is the most extreme I’ve seen, a typical variance with almost any campaign is between 10% and 30%. In one recent campaign, I saw four top-tier vendors measure viewability at rates that varied by more than 30%, including 32%, 40%, 56% and 64%.

Truths like this exist because there is no set standard for how to measure viewability. Many brands look to the MRC for guidance and standards, but the MRC only verifies that viewability vendors measure as they say they do – that’s it. Viewability vendors can measure using browser optimization and/or page geometry, and can become certified with either or both methodologies.

It’s impossible to set threshold for viewability when vendors aren’t required to measure the same way, and variances are known to be this wide.

Flying Blind

Worse than the lack of standardization is that the focus on viewability blinds advertisers from their true campaign objectives. Assigning a viewability threshold to a programmatic campaign can actually sabotage conversion rates.

Viewability thresholds tie the hands of optimization analysts, requiring them to adjust audience targeting and media bidding to buy only those impressions that are deemed by a client’s viewability vendor as “viewable.” This leads to strict filters that often time overfilter impressions. Ad placements that could, in reality, be viewable to consumers can sometimes be filtered out pre-bid as “non-viewable.” This can hurt the scale of an advertiser’s audience and therefore undermine performance.

I’m in no way saying that viewability shouldn’t play a role in a campaign. It absolutely should. But since it’s still evolving and its measurement is not yet unified across all vendors, conversion rates should be the prioritized metric in direct-response campaigns.

Conversions are the true indicator of a qualified consumer viewing and engaging with an ad. Viewable impressions mean nothing to the objective of a campaign if the eyes on an ad belong to uninterested consumers. Readjusting a performance campaign’s focus from viewability to conversion addresses the importance of audience qualification.

Conversions are the ultimate measure of success for a performance campaign – whether it’s a form-fill, purchase or whatever a brand may decide on. While strict viewability requirements force brands to sacrifice conversions, flexible viewability rates allow campaign managers to optimize audience targeting to conversions, which is the most telling sign that an ad has been viewed, hopefully, by the right person.
I call on brands, agencies, ad tech vendors and publishers to talk more openly about the realities that surround viewability, and to work together toward a standardized solution. By collaborating as partners, rather than clients and service providers, commonalities will be found and discrepancies will narrow. Viewability will become a deliverable expectation, rather than just a numbers game.

Follow Eric Bosco (@ericbosco), ChoiceStream (@ChoiceStream) and AdExchanger (@adexchanger) on Twitter.

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  1. Very important to be clear. Viewability does not mean consumers actually saw the “viewable” ads. Viewability is the ‘potential’ to be seen.

  2. Hi Eric, thank you for your attention to this truly important topic. You’re correct that MRC doesn’t mandate the precise methods vendors must use to measure viewability, and that’s for a host of reasons that we can discuss at length. But MRC’s accreditation process involves much more than simply confirming that vendors do what they say they do; their systems are rigorously tested and assessed by independent CPAs and MRC-member audit committees against a range of industry measurement standards, and only become accredited if determined to be in compliance with those standards.

    That said, MRC recognizes viewable impression counting discrepancies are still a problem, and we’re engaged in an ongoing effort to eliminate them by identifying and addressing any remaining systemic issues that are causing discrepancies in accredited vendors’ reporting of desktop viewable impressions. In fact, we recently announced the results of a 3rd phase of this study (see results summary here). As a result, the MRC Viewable Impression Measurement Guidelines will be updated shortly to address certain findings identified through this reconciliation process.

    This is an ongoing process and we’re confident that the industry’s attention to fine-tuning the details will lead to the reduction and, ultimately, the elimination of this problem. I encourage you to visit or

  3. I’m glad someone is shedding light on the growing problem of relying on questionable viewability metrics for planning and optimization. Beyond the discrepancies in viewability, there is also the issue of page quality. If a “viewable” ad is one of 10 ads on a suspect page, it has no more value than a non-viewable ad. Then there’s fraud, excessive frequency and a host of other issues.
    Bottom line is there are problems in the ecosystem and advertisers should have reasonable expectations. 100% viewability is a nice idea, but at what cost and based on whose metrics?

  4. The advertisers are completely in their right to ask for viewability. The problem isn’t them, it’s the standards groups.

    Sadly the IAB and MRC are both design-by-committee when it comes to technical matters, without any real technical expertise. The viewability standard is incomplete considering how many ad formats there are and offers no information about how the measurement process should work and there’s clearly no test suite, just some basic checks while charging a ridiculous amount for the “audit”.

    We dont need more BS “conversations” like that useless 3MS initiative posted above that won’t actually solve anything. Why commission another study? We already know what the problems are. A few good software engineers led by a competent project manager can make a better standard and handle all the audits in about 2 weeks.

    Until we get rid of the politics and committees and conversations and actually focus on getting this solved by the right team, things will never get better…