After qualifying as an engineer in the motor industry and spending seven years as a design engineer, Derek entered the Patent profession, qualifying in 1972 and becoming a partner in Jensen & Son in 1976.
Having been involved in the motor industry throughout his career, Derek is probably Europe's most experienced private practice attorney in his field.

Derek has particular experience in mechanical and electrical engineering generally, in materials handling, storage, medical equipment, in the electronic field and computers - particularly in satellite and communication systems and solid state technology. Apart from specialising in the motor industry, both in Patents and Trade Marks, he has extensive Trade Marks experience, particularly in major overseas filing programmes.

Derek is currently involved in one such programme, involving nearly 1,000 Trade Mark Applications on some 90 countries. He has also been involved in patenting computer-related inventions and was responsible for establishing one of the first successful cases in this field (Gever's Appln. 1970 RPC).