Which Publishers are "Lazy Loading" or "Just-in-Time" ad serving succesfully?

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Published by: Mike McLeod , PGA TOUR
Published on: April 15, 2014

Hello Monsters -

Working on options/research around the topic of display viewability.

Which publishers out there have implemented "just-in-time" or "lazy loading" of ads slots?

Bonus points if you can point to a collection of best practices out there.

Daily Double goes to anyone who is doing it using DFF (XFP-Premium) and GPT tags....

- Mike McLeod, Ad Tech, PGA TOUR Digital


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New information...

DoubleClick pointed me to this help center article - which speaks to "infinite scroll" and "refreshing specific ad slots"


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Ian -

Thank you for the great information.

Well aware of the inventory implications.

MSNBC/NBC News used to do this but it looks like they've stopped.


It shouldn't be that hard to do this with GPT. I do not believe it can be done with single request mode as ads are fetched and counted when you call the googletag.defineSlot lines. However, as long as you are not using SRA mode, simply delay executing the googletag.display lines until its time to display the ad.

I'd suggest that best practice if you want to ensure viewability is to not load the tag until 50% of the ad unit area comes into the viewport, though you may want to experiment with this -- delays in loading might mean that it makes more sense to load immediately so that there is enough time for the ad to be in viewport to register as viewable if the user is scrolling.

I would think about/be more concerned about the monetization implications of this rather than technical issues. This WILL reduce your saleable ad inventory. While one theory goes that was already priced into the market, and thus your total revenue shouldn't change (i.e. you should be able to charge higher CPMs now that you're 100% viewable), in reality I doubt this to be the case. People are more sensitive to price increases than decreases and raising your rates would be hard.

Maybe it might be better to simply drop low-viewability placements and/or lazy-load only the low-viewable placements.

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Just a note - I've found one or two people offline - when I know more I'll post here in case others are interested....

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Benny -

Thank you. That is a concern. We'll have to weigh the cost/benefit of implementing something that isn't supported. We may have to run the risk in order to increase viewability.

Lazy loading your ads with your DFP tags will likely void your DFP support, or so I heard. So far no one I know on DFP want to have their support voided, I suggest great caution on such matter.

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