Dare, one of the UK's leading digital creative agencies, has sold a majority stake to Canadian marketing services company Cossette in a complex deal that could eventually value the firm at over £20m when the takeover is complete.

Cossette has paid an initial £10m to take a 65.4% stake in Dare that will see the Canadian company immediately buy out the 30% stake held by ad agency Bartle Bogle Hegarty.

The Canadian media group also owns Miles Calcraft Briginshaw Duffy, the London ad agency that recently made former Big Brother contestant and media executive Jonathan Durden a partner. It is also home to PR group Band & Brown and branding consultancy Identica.

Dare, which counts BBH co-founder John Bartle as a non-executive director, has clients including Vodafone, Lynx, Barclays, ITV and Sony Europe.

In a six-year, three-part deal Cossette will have options after the third and fifth years to buy further 17.3% stakes in Dare - subject to the agency achieving performance targets.

The deal is uncapped, meaning that the total valuation will be determined based on future growth and profit margins.

In the 2007 fiscal year Dare had a total gross income of around £9.8m and staff of 130.

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