Ofcom, which published its findings this morning, ruled that The Number neither sought nor obtained David Bedford's permission to be caricatured and concluded that The Number, which owns the 118 118 service, breached the Advertising Standards Code.
Crucially, Ofcom's ruling does not ban The Number from using the Bedford likeness in its advertising, which has helped the service become the most successful of all of the new directory enquiry services since the sector was deregulated last year.
In a statement Ofcom said: "It would be disproportionate to direct that the advertisements are not shown in future and we consider that the publication of the finding of breach by the Content Board is a sufficient resolution of the matter.
"The Number's appeal against the finding of breach therefore fails, but we make no further direction in relation to the breach," it said.
Ofcom added that it was "not satisfied" that Bedford had suffered actual financial harm, which could hurt any claim for damages.
In response to Ofcom's ruling The Number issued a statement welcoming the decision and said it would continue to use the runners in its advertising.
William Ostrom, communications director at The Number, said: "We welcome the decision to be able to keep using the runners. Ofcom has made the common sense decision saying we did caricature, but that no damage has been done. For us we are only interested in advertising our service."
In its ruling Ofcom noted that Bedford delayed for about six months before making a complaint, during which time The Number committed itself to very substantial expenditure in developing a brand, but it does not stop Bedford now pursuing legal action.
Bedford first threatened legal action in October accusing The Number of stealing his likeness for its Zapatista-moustachioed runners.
Bedford broke the 10,000 metres record in 1973 and, like the two runners featured in the WCRS-created advertising campaign, sported a Zapatista moustache and a vest.
Lawyers acting for Bedford were asking for £200,000 in damages. With the Ofcom ruling on his side, his lawyers could now push ahead with a claim against The Number.
The Number has consistently denied that it modelled its campaign on Bedford, arguing that the look was a widely popular one in the decade.
In its defence The Number has said it used pictures of another runner, the American Steve Prefontaine, who was killed in a car crash in 1975. Prefontaine did not sport the Zapatista look.
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