The program resembles a standard audience extension, a strategy offered by platforms including Facebook and Google, that increases the relevant scale these companies can offer to advertisers by bundling in third-party audiences, according to Messer. 

But audience extensions typically lack transparency, with advertisers unsure as to where their campaigns ultimately ran. With Interest Collectives, by working only with vetted publishers, Flipboard offers its brand partners curation as a service.

“They are curating a marketplace on behalf of their publishers and splitting the revenue with them,” Messer said. “Publishers will always welcome direct demand, but the scale needs to be there for it to be worth their while.”