Details of the settlement will not be released until the lawsuit is ended in London's High Court later today. However, a report in the Daily Mirror says Cowell is happy with the amicable settlement.
"We're delighted with the outcome. People think we hate each other but we don't. We're good friends," Cowell said.
Fuller, who is best known for managing the Spice Girls, owns 19 Entertainment, the company that produces the hugely successful 'Pop Idol' format.
He had accused Cowell of ripping off the 'Pop Idol' format to make his own show 'X Factor', which has turned into an equally successful reality TV show for ITV.
The court case was adjourned twice last Wednesday and once on Thursday before lawyers for the pair decided an out-of-court settlement was achievable.
Details of a new contract that tie Cowell to Fox Network's 'American Idol' are expected to be announced in the next few days.
Whatever happens, Cowell will be returning as judge in chief of the hugely successful 'American Idol', the US version of 'Pop Idol', which is set to return for its fifth season in January. 'American Idol' has made a star out of Kelly Clarkson.
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