RDF will to pay an initial £8.4m for the business and, if targets are met, an additional £5.6m by January 31 2007.
The deal puts RDF in a good position to fill broadcasters' out-of-London and national quotas because IWC is headquartered in Glasgow.
Other flagship IWC shows include property show 'Relocation, Relocation' and comedy series 'Meet the Magoons', both for Channel 4, and BBC documentary 'No Sex Please... We're Teenagers'.
As part of the deal, non-executive shareholders including newsreader Kirsty Wark, Muriel Gray and John Boyle wil receive a one-off payment of around £1m each.
The deal will be the second production company merger this week, after 'Footballers Wives' creator Shed acquired indie Ricochet, which produces 'Supernanny', in deal worth up to £30m.
It is also RDF's second acquisition this year, after taking complete control of indie Touchpaper in a deal worth £2.7m in August.
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