YouTube could be gearing up to let brands utilize third-party services to help them determine which ads are actually being seen by viewers. By doing so, the company could help brands verify the benefits of doing business with the video social network — especially important following complaints by the likes of Unilever and Kellogg’s.

As reported by the Financial Times, some brands are concerned that YouTube isn’t being transparent with its reporting. These discontented brands have been buying ads but say they are not sure whether those campaigns are actually being viewed. There are a variety of reasons this could be happening, such as ads being located outside a person’s screen (chances are that if you have to scroll, videos may not be viewed) or the potential viewer just up and leaving a page before it’s been fully loaded.

Although Google does provide advertisers with analytics through its Active View offering, several advertisers have made it clear that they are looking for ways to confirm this information. Rather than just taking YouTube’s word for it, brands could use these third-party services to learn whether their money is being well-spent and whether their campaigns need to be retooled or repositioned.

This decision to allow third-party verification could be fueled in part by reports in May that Kellogg and other brands would be reigning in their marketing dollars from not only YouTube, but also Facebook, over the social networking companies policies prohibiting such outside verification.

At the time, Rino Scanzoni, chief investment officer of the world’s largest advertising media company GroupM, was quoted as saying:

“Third party verification is a critical component to responsively measure ad viewability. The vast majority of publishers agree to it and the few that don’t will be adversely impacted with significantly reduced spend or be completely removed from our preferred vendor list.”

Sources told the Financial Times that YouTube is planning to let third-party verification groups insert code onto its site, enabling these independent entities to collect data on the position and context of the ads. YouTube could roll this option out before the end of the year and will likely see strong interest from the likes of ComScore, DoubleVerify, and Integral Ad Science.

We’ve reached out to YouTube for comment and will update if we hear back.

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