Companies that provide “brand safety” lists often use outdated terms and obscure how their keyword targeting works, said Nandini Jammi, a marketing industry advocate. “These are not made clear to advertisers,” she said. “Everyone is doing it. No one is thinking about it.”

At the other end of the chain, news publishers struggle to find out which brands are blocking what, making it harder to hold the brands to account. The companies that administer the ad blocking profit from each block, so have little incentive to help.

WPP agency GroupM said it’s trying to get brand marketing teams to making their blacklists more intelligent so more ads reach trusted news sources.

Rather than blocking “Covid-19,” they block a combination of words such as “Covid-19-Miracle Cure” or “Covid-19-Refrigerated Truck” so that ads don’t appear alongside irresponsible or particularly unpleasant news stories, said John Montgomery, the head of GroupM’s global brand safety practice.

“The technology is not the enemy,” he said. “It’s the way we use it.” 

Unpicking the chain of arrangements that are pulling advertising away from news is complex because publishers are the last link in a vast online ecosystem. Digital ads are created by agencies at global companies such as WPP Plc and transmitted via technology platforms including Alphabet Inc.’s Google and intermediaries like IAS and DoubleVerify. An ad flows through a warren of automated marketplaces and is sold a split-second after you click a link to the page where you see it. A myriad of suppliers trade and verify the content, while others gather data to target it better.

It’s turned what used to be a simple agreement between a paper’s ad department and a brand marketing representative into an opaque process that’s dissipated responsibility and accountability.

Google rejects any blame for the boycott of Covid-related news, saying there are no technical or policy reasons to stop publishers monetizing coronavirus-related content on its platforms.

“We are in constant discussions with our publishing partners, advertisers and agencies on how we can continue to support a sustainable future for news,” said a Google spokesperson.

Ad dollars have been draining from the news business for a decade for reasons that reach beyond the pandemic, said Montgomery at GroupM. As the big social media platforms developed sophisticated filters to keep brands safe from harmful or toxic content, they’ve captured more of the ad dollars that once went to news. The result is that “media planners have been trained not to need news any more,” he said.