Duncan Longstaff



Duncan is a Principal in the law team and an expert litigator, having conducted major complex IP litigation for both multinational and listed Australian companies. He has a particular interest and practice focuses on patent disputes, including in the pharmaceutical, biotechnology, medical device, mining/energy and information technology sectors.


As an expert litigator, Duncan conducts major complex IP litigation for multinationals and listed Australian companies in the Federal Court of Australia and High Court of Australia, as well as smaller commercial, administrative (Patent Office, Trade Marks Office, Australian Administrative Tribunal, Copyright Tribunal) and other disputes. He has been involved in pre-litigation and strategic planning, pursuing and defending urgent interlocutory injunction applications, lengthy trials, appeals and mediations.

Duncan has played a significant role in several major Australian patent cases throughout his career. He has provided extensive pre-litigation advice to numerous patentees/applicants and potential opponents/defendants, particularly in the pharmaceutical and broader therapeutic goods sectors. His scientific qualifications (cell and molecular biology) enable him to quickly grapple with technical subject matter and work effectively with clients and expert witnesses.

Duncan has also acted in numerous commercial, contentious and advisory matters relating to copyright, confidential information, trade marks, trade practices, privacy and competition law. He regularly collaborates with patent and trade mark attorneys in drafting and prosecuting patent and trade mark applications and devising IP strategies.

He was identified by Legal 500 as a “Next Generation Lawyer” in 2017 and a “Rising Star” by Managing Intellectual Property in 2018.


  • Master of Intellectual Property Law, University of Melbourne, Australia, 2014
  • Bachelor of Laws with first class Honours, Australian National University, Australia, 2006
  • Bachelor of Science (Double Major Cell & Molecular Biology), Australian National University, Australia, 2006


  • Intellectual Property Society of Australia and New Zealand (IPSANZ)
  • American Intellectual Property Law Association (AIPLA)
  • International Trademark Association (INTA)


  • “Next Generation Lawyer”, intellectual property (2017) – Legal500
  • “Rising Star”, intellectual property (2018) – Managing Intellectual Property