The imperative of brand safe ad placement comes at a cost, including slower loading publisher webpages.

The variety of brand safety tools and tags causes latency on publisher sites, increasing page load times and ultimately hurting publisher revenue, according to data from ad tech consultancy RedBud and the Association of Online Publishers.

Between April and September, RedBud analyzed 128 live campaigns across 11 websites published by AOP members. AOP members include The Telegraph, ESI Media, Dennis Publishing, TI Media and MailOnline. The study found the delay caused by keyword blocking wrappers was often between two and four seconds. According to Google, 53% of people will leave a mobile page if it takes longer than 3 seconds to load. The lag leads to ads not always loading, increasing the difference in the impressions the publisher serves and the impressions the advertiser counts as having loaded. The study found brand safety wrappers and keyword blocking tags are the most common cause of discrepancy between ad sellers and buyers on the simple matter of how many ads were displayed.

The median ad discrepancy was 8.4% if a keyword blocking tag was present compared to 3.4% when no tag was present. This difference means publishers are often faced with agencies refusing to pay for some impressions because their own data shows that the ad hadn’t loaded in time to be in view.



While a certain level of difference between the number of impressions served by the publisher and the creative served is to be expected — publishers don’t see whether the impressions are blocked by the technology — the study noted these differences were significant due to keyword blocking tags.

“The challenge we have is that we don’t get visibility of the full extent of this, it’s a bit of a silent assassin,” said one magazine publishing executive, speaking anonymously.

Publisher revenue is dented on several sides through blunt brand safety tools. Another pain point is that, due to overzealous blocking of keywords that may seem risky, publishers report that anything from between 40% and 60% of healthy inventory is blocked from running ads.

The industry appears to be making improvements, albeit slowly. Research conducted for Digiday by RedBud in March this year found that between 10% and 21% of the total weight of a website come from brand safety, viewability and verification tag. Publishers have previously commented that these tags can add up to six seconds in loading time.