Keith specialises in infringement, ownership and validity disputes, licence negotiation and drafting. He advises clients in a range of sectors notably food, fashion and luxury goods, household cleaning and personal care products, toys and sports equipment, financial and other services.

Keith is a member of LES, FICPI and ECTA and was from 1995-2000 visiting professor at Universidad de Alicante and from 1998-2007 honorary lecturer at the University of Manchester, teaching on its intellectual property certificate course. He was one of the first attorneys to be registered as a certified trade marks and design civil litigator under the Trade Marks Attorneys Order 2004 and is trained as a civil and commercial mediator following the EU Model Code of Conduct for Mediators.

Keith graduated in law from Cambridge University and in science from the Open University (majoring in environmental monitoring/control engineering). He taught intellectual property, trusts and contract law at the University of Manchester before joining Marks & Clerk in 1986 and he became a partner in 1993. He was appointed chairman of Marks & Clerk in 2008.