
Maddocks joined the Sydney office from New Zealand in September 2007 to replace Danny Searle, who left to take up the role of chairman and chief creative officer at BBDO Singapore.
On his resignation, Maddocks said: "I've thoroughly enjoyed my 12 years with the Clemenger Group. At both Colenso and Clemenger Sydney I have worked with some of the industry's best talent and I'm grateful to the clients, staff and management for the amazing support I've received over that time."
He added: "However I've decided I want to work with clients under an alternative agency structure. I'm in the early stages of discussions with several interested parties on how that might look. Until then, my focus will be on helping Andy, Al and the guys work through the transition."
Managing director of Clemenger BBDO Sydney, Andy Pontin, said: "Rich is a great talent and a great bloke, so it's a shame to see him go. He has helped build an incredibly strong creative department so we're in good shape. Over the next six months, Rich will be a key contributor in helping us to recruit his successor to ensure minimal disruption to our clients."
Maddocks' resignation comes after Clemenger Melbourne ECD, James McGrath, was appointed creative chairman for the entire Clemenger BBDO Group and Ant Keogh was promoted to fill McGrath’s role.