School of Law

Professor Roger Cullis, BSc, DMS, PhD, CEng, CPhys, FInstP, FIET, CPA


Visiting Professor

Room Number: Lincoln's Inn Fields


Roger Cullis is a Visiting Professor in Intellectual Property Law and Technology. He graduated, in Physics and Mathematics, from Queen Mary College, London in 1959 and worked initially as a Research Physicist and Development Engineer in the electronics industry where he prepared a preliminary design study for the first transistors used in transatlantic submerged repeaters and developed novel silicon planar epitaxial flip-chip integrated circuits, gaining fifteen patents for his inventions. He then trained as a Patent and Trade Mark Attorney and worked, at International Telephone and Telegraph Corporation, on corporate plans for the globalisation of the semiconductor industry and as a technical consultant to the UK Ministry of Technology before joining the Rank Organisation as Deputy Patents Manager. In 1982, he was appointed Patent and Trade Marks Controller of Ronson International Ltd based in Switzerland and, following a brief spell as a trade mark licensing consultant to associated offshore companies in the Bahamas, Turks and Caicos, Liechtenstein and the Isle of Man, he joined the National Research Development Corporation (NRDC) as a senior patent attorney specialising in cutting edge physics, electronic engineering and communications inventions. In 1989 he advised Queen Mary CCLS on the creation of its MSc in Management of Intellectual Property. Between 1990 and 2011 he taught and examined some 800 postgraduate students and helped develop this course into a worldwide leader for the academic training of IP professionals. He has served on the Councils of the Chartered Institute of Patent Attorneys and the Newcomen International Society for the Study of the History of Engineering and Technology and was a Supervisory Examiner of the UK Joint Examination Board for patent and trade mark attorneys.


Professor Cullis’ special interest is in the dynamics of innovation for which he has devised a black box model in which the development of an innovation is represented as a trajectory in multidimensional phase space. For empirical research he has assembled a “big dataset” comprising some 9,000 patents and 63 journals describing aspects of the initial commercial development (including two Nobel Prize winning inventions – holography and the MRI scanner) of the National Research Development Corporation, the world’s first technology transfer organisation, following its creation by the Development of Inventions Act, 1948.

He currently has one Doctoral student: Yingying Chen - "Patents as an investment tool –  the development of the business model of a patent”.

He has also completed PhD supervision with the following student: Deborah Sewagudde - “Why did video screens get slimmer – a study of the role of patents in the commercial development of organic copolymer semiconductor materials and devices”.



  • Within the BBC Microcomputer – a reference manual for assembly language programmers
  • Patents, Inventions and the Dynamics of Innovation – a multidisciplinary study
  • What makes a successful innovation – four inventions which changed the world economy.

Patent applications prepared and prosecuted

Many dozens, including:

  • EP0269624B1 Fibre optic laser and amplifier which covers the erbium doped fibre optic amplifier, one of the ten most important electronics inventions of the 20th Century and the basis of fibre optic communications
  • WO 98/53351 Optical Photonic Band Gap Device and Methods of Fabrication thereof, the basis for Mesophotonics Ltd’s spin-off from the University of Southampton.

Patents for my early inventions

  • GB1001150 Transistor with triangular die
  • GB1010404  Junction-gate field effect transistor formed by subepitaxial planar diffusion
  • GB1015588  Bipolar transistor with coplanar collector, base and emitter electrodes formed on a substrate which provides a path of lower resistance
  • GB1022366  Semiconductor devices having solder coated coplanar electrodes for direct flip-chip mounting
  • GB1023532  Method of etching a graded metallic film of gold and chromium
  • GB1027550  Orientation of flip chip electronic components using reference marks on the reverse face of the semiconductor die
  • GB1028485  Neutralising the effect of run-ahead in double diffused silicon planar transistors
  • GB1028956  Enhancing the resistance of planar junction devices to avalanche breakdown
  • GB1035727  Use of a Darlington pair arrangement to increase the linearity of current gain of a bipolar power transistor
  • GB1039257 Semiconductor die mounting method providing insulation high thermal dissipation and electrical isolation
  • GB1039915  Four and five layer switching devices for flip chip mounting
  • GB1066911 Preparation of semiconductor wafers with reduced susceptibility to imperfections
  • GB1084937 Fabrication of complementary insulated gate field effect transistors
  • GB1115249 Fabrication of high reliability bipolar transistors using a probe surface field effect transistor
  • GB1195259 Photolithographic method with enhanced accuracy for transistor fabrication.