Kitcatt Nohr launched in January 2002 with financial backing from Mentor Marketing. It is led by creative partner Paul Kitcatt, managing partner Marc Nohr, client partner Vonnie Alexander and chairman Jeremy Shaw.
The partners have now bought up shares held by Mentor, which had an original investment team that included industry heavyweights Clive Mishon, John Hooper and Colin Lloyd.
Mishon retains a minority holding in the agency and will continue as a non-executive director. A further non-executive directorship is yet to be filled.
Nohr said: "The relationship with Mentor Marketing & Investment has been hugely positive for the agency and we're delighted to have achieved a growth in fee income from zero to £3m in four years."
"Buying out our investors now is a sign of our confidence that the agency will continue to develop into one of the UK's leading independent integrated agencies."
Mishon said: "After four tremendous years Kitcatt Nohr is now in charge of its own future having delivered a return on investment worthy of the original investors' confidence."
The agency's clients include the Department of Health, COI, Virgin Holidays, Friends Reunited, Channel 4, Eve Magazine and The National Blood Service.
Meanwhile, Kitcatt Nohr has handed the role of planning director to Lazar Dzamic, planning director for sister digital agency Underwired.
As well as joining the Kitcatt Nohr team, Dzamic will continue his role at Underwired and will split his time equally between the two shops.
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