Lord Alan Sugar was created to remove a tweet promoting a teeth whitening product after breaking ad guidelines.
The student host, 73, said the Stylsmile toothbrush kit would be a “perfect Christmas present,” but made it unclear that the message was an ad, the Advertising Standards Authority (ASA) said.
Lord Sugar is a director of the manufacturer Stylideas Ltd and owns a 50% stake in the company – and shares it with a previous winner of his popular TV show.
“If you know someone who craves whiter teeth, this is the perfect Christmas present for them,” he tweeted on December 9 last year, including a link to the product web page.
The ASA said Lord Sugar’s connection to the company was known because it had been made public to millions of viewers during a prime-time show.
Marketing guidelines say that ad communication should be clearly identifiable as such and make their commercial intent clear if not clear from context.
Messages must contain at least the hashtag £ ad.
The ASA said Lord Sugar’s tweet had not “ immediately made clear ” his commercial interest in the company to consumers.
It ruled that the ad should not be reproduced in the form complained of, adding that future posts from Lord Sugar and Stylsmile should make clear all commercial intentions in their posts.