After monitoring more than 60 sponsorship campaigns across a wide range of commercial broadcasters, Ofcom found several programmes in breach of rule 9.13 of its code, which says: "Sponsorship must be clearly separated from advertising. Sponsor credits must not contain advertising messages or calls to action.
"In particular, credits must not encourage the purchase or rental of the products or services of the sponsor or a third party".
Programmes containing breaches included Channel 4's 'Big Brother' and '4Homes' programming, Five's 'Weather' and 'The Gadget Show', ITV's 'GMTV Weather', 'The X Factor' and 'The Alan Titchmarsh Show', Living's sponsorship of daytime programming, and UKTV's sponsorship of 'Your Natural World' programming.
Ofcom said that the credits were generally found in breach of the code due to the use of promotional language to describe the sponsor's products and/or services, which in Ofcom's opinion amounted to advertising messages.
Ofcom said: "Rule 9.13 permits brief descriptions of the sponsor's products/services on the basis that these can help identify the sponsor. Ofcom has judged that the references in the following cases went beyond the brief descriptions allowed under Rule 9.13."
In the case of Channel 4's 2008 version of 'Big Brother', which was sponsored by Virgin Media and Virgin Mobile, Ofcom found two separate credits to be in breach of the code.
One credit featured the voiceover: "Ellie and Ruth use their Virgin mobiles to get perks at V Festival without having to flash a roadie like usual", with a caption that read: "Big Brother sponsored by Virgin Mobile 0800 052 0444".
Another credit featured a voiceover that said: "Len's fibre optic cable is just like his women, fast and easy", along with the caption: "Big Brother sponsored by futuristic Fibre".
Ofcom ruled that the reference to being able to get "perks at the V festival" was a special promotional reference to the benefits of being a Virgin Mobile customer.
It said that the use of promotional language, such as "fast and easy", to describe the sponsor's products went beyond brief descriptions of the sponsor's business and amounted to advertising messages.
Ofcom intends to repeat its monitoring exercise of sponsorship campaigns in three months' time.