Half an ad has been enough to comprise a digital "view" according to the industry's Media Rating Council for the past three years, but the group may consider toughening its oft-maligned standard to require every single ad pixel displays.

That would close some of the "viewability" gap between the industry standard and the much stricter requirements of enormous ad buyers including Unilever and GroupM.

They would effectively align on display ads, where GroupM already demands that 100% of an ad shows on-screen for any amount of time and the Media Rating Council has required 50% to appear in view for at least one second. And it would get them closer on video. GroupM needs every pixel of a video ad to appear on-screen for at least half the purchased time or 30 seconds, whichever is longer, and requires consumers to press play. MRC requires half of a video ad to be in view for at least two seconds before it calls it "viewable."

Procter & Gamble Co. Chief Brand Officer Marc Pritchard has called on the industry to rally around the MRC rule for the sake of simplicity. Unilever Chief Brand Officer Keith Weed recently called on the industry to rally around the GroupM standard.

Some in the industry believe the MRC will move to the 100% standard to put digital media more on par with TV and other media. MRC Senior VP David Gunzerath said in an email that the group may consider such a move.

"We're constantly reviewing the measurement standards we've written to assess their continued relevance and effectiveness," Gunzerath said. The group has "no imminent plans to change the current requirements" but it "definitely" will consider the digital viewability standard as it begins a project on cross-media audience measurement later this year. That effort will develop standards for applying audience measurements such as demographics and gross rating points now used for TV to digital media as well.

"It's possible we will" consider a 100% in-view standard, Gunzerath said, "and it's possible we won't." But the decision won't just be based on industry feedback, he said. It will also be based data and analysis, as was the case with the original standards.

The idea behind the current definition of viewability was always that it provided consumers an "opportunity to see" the ad, akin to the way impressions are defined for TV and other media. But it has also drawn much derision, including from Unilver's Weed in an appearance at the Cannes International Festival of Creativity last month.

"Imagine you bought a tub of Ben & Jerry's ice cream and it was half full," Weed said. "It doesn't pass what I call the 'mom and dad test.'"

Certainly GroupM would welcome an MRC move to 100%, said Ed Gaffney, director of implementation research.

"We think it creates a more comparable impression across media channels," he said. "TV ads that hang off the screen, you get a make-good. Print ads that aren't fully on the page, you get a make-good. Most media are completely there."

Most publishers have agreed to work with GroupM's standards, Gaffney said, and industry performance has improved to the point that more inventory meets those requirements, he said.