NEW YORK: Influencer marketing is growing in popularity with brands and while most influencers are aware of the need to disclose any commercial arrangement they may have, a new survey has found that one in four has been asked not to reveal this to followers.

The figure comes from influencer marketing and media platform SheSpeaks, which surveyed 347 influencers. Almost all (95%) said they were upfront with their audience about being paid by a brand; and almost as many (91%) said that a brand itself had requested such disclosure.

But 25% also reported that they had been expressly asked by brands not to divulge the information that they were being remunerated, according to Advertising Age.

The Federal Trade Commission stipulates that any compensation, including free products, should be disclosed, but its critics have said it needs to be clearer about its policies and more consistent in their enforcement.

So, for example, influencers may be using hashtags like #ad and #sponsored to alert followers to the commercial nature of a post, which are deemed to be acceptable if they're at the beginning of a post, but other widely used tags like #sp and #spon aren't.

"If consumers don't read the words, then there is no effective disclosure," Michael Ostheimer, a deputy in the FTC's Ad Practices Division, told Bloomberg last week.

"If you have seven other hashtags at the end of a tweet and it's mixed up with all these other things, it's easy for consumers to skip over that. The real test is, did consumers read it and comprehend it?"

The issue hit the headlines last month when Warner Bros Home Entertainment settled FTC charges that it failed to adequately disclose that it had paid online influencers to post gameplay videos.

"Consumers have the right to know if reviewers are providing their own opinions or paid sales pitches," said Jessica Rich, Director of the FTC's Bureau of Consumer Protection. "Companies like Warner Brothers need to be straight with consumers in their online ad campaigns."

They also need to better brief their influencers, according to the SheSpeaks survey, which reported that insufficient briefing was a top three challenge for this group, the other two being balancing brand message and tone of voice, and optimising content by having brands share their work.

Aliza Freud, founder and CEO of SheSpeaks, claimed that using influencer content as digital ads can perform 800% better than traditional digital ad units.

Data sourced from Advertising Age, FTC, Bloomberg; additional content by Warc staff