NEW YORK: Following feedback from publishers about Instant Articles, Facebook is revisiting its ad policies concerning the product, amid concerns that publishers are not generating as much revenue as anticipated.

Publishers who signed up to the Instant Articles program are struggling to make as much money from it as from posts on their own websites because of restrictions imposed by the social network, sources have told the Wall Street Journal.

The feature, which links articles to a user's News Feed and is supposed to load much faster than a standard webpage, was rolled out to all iOS devices last month.

However, publishers – including such big names as The Washington Post and New York Times – have been limited in what content they can link to Instant Articles.

Currently, each Instant Article is allowed only one 320 x 250 pixel banner for every 500 words of content whereas a publication's website would typically have three or four such placements in the equivalent space.

Furthermore, publishers are not allowed to use "rich media" animated or interactive ads and they cannot sell Facebook-only campaigns.

While the publishers are reported to have confidence in the platform for the long-term because of the potentially huge scale of its reach, Facebook has accepted that it needs to address their immediate concerns.

Michael Reckhow, Facebook's product manager for Instant Articles, confirmed that changes to its ad policies are being tested, including allowing more ads per article and removing restrictions on ad formats.

"It's early days with Instant Articles, but one of our principles from the beginning has been to work collaboratively with our publishing partners to understand their needs and shape the product," he said.

"We're currently working closely with publishers to understand how their advertising in Instant Articles compares to the mobile web so we can deliver results, while maintaining a great reading experience for people.

"We've made numerous improvements to the advertising capabilities over the past few months and will continue to iterate based on publisher feedback to improve the product."

Data sourced from Wall Street Journal; additional content by Warc staff