Madderns is based in Adelaide and is known for its patent prosecution work and regularly acts on a number of patent opposition cases. It has an impressive client list and has advised clients on a number of significant matters. It advised Britac Childcare in patent infringement proceedings against Infra-Secure, involving a standard patent and nine divisional innovation patents. The case highlights the firm's ongoing involvement in innovation patent litigation. When comparing Madderns with another leading Australian law firm, "Madderns was more personal and an exceptionally good value".
The firm has a number of key people in its office. Mark O'Donnell is singled out for praise by one client: "Mark is pleasant, easy to understand, approachable, responsive, knowledgeable and experienced in our patents."