A campaign by Snickers paying Katie Price and Rio Ferdinand to tweet about the chocolate bar has been cleared of breaking UK advertising rules, in the first ruling by the ad watchdog involving marketing on Twitter.
Mars, the parent company of Snickers, paid the celebrities to make five tweets.
The first four tweets were seemingly odd statements incongruous with the celebrities' usual behaviour and made no reference to Snickers.
Katie Price tweeted about China's GDP and the Eurozone crisis and Ferdinand talked about knitting a cardigan. The fifth tweet then promoted the chocolate bar.
The final tweet, which was accompanied by a photo of the celebrities holding a snickers bar, used the strapline "you're not you when you're hungry" and the #spon suffix, short for "sponsored" tweet.
It also mentioned @snickersUK, the official Snickers Twitter account.
The Snickers campaign also included celebrities such as Sir Ian Botham and former X Factor contestant Cher Lloyd. However, the ASA did not receive complaints about their Snickers-related tweets.
The Advertising Standards Authority, which has never investigated or ruled on advertising on Twitter, received two complaints that it was not obvious that the tweets were marketing communications by Mars.
Mars said it "considered in detail" the extent to which the tweets were marketing communications and believed only the last one needed to be identified.
Mars argued consumers could not have been misled into making a purchase by the first four tweets as their meaning only became apparent once the campaign was revealed with the fifth message.
The ASA said all five tweets should be considered to be part of an "orchestrated" advertising campaign and disagreed with Mars that the first four only became marketing communications after the final tweet was posted.
However, the ASA said the final tweet was so clearly highlighted as an advertising campaign that consumers were not likely to be misled.
"We considered the combination of those elements [in the final tweet] was sufficient to make clear the tweets were advertising and that consumers would then understand each series of tweets was a marketing communication," said the ASA.
"We considered it was acceptable that the first four tweets were not individually labelled as being part of the overall marketing communications. We therefore concluded that the ads did not breach the [advertising] code."
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