our key people

Jan Oosterom – Managing Director

Jan has over 25 years' expertise in the insurance broking industry. Prior to joining Howden, he was Chief Operating Officer for the Netherlands broker Concordia de Keizer and has been Manager of Hull and Cargo at Marsh.
He holds a law degree from the Erasmus University in Rotterdam


Martin Besemer – Director

Martin has over 25 years’ experience in insurance with a specialist interest in the Marine sector.  He has held previous roles as a Specialist Broker and Account Director working with the Marine industry. Martin joined Howden to lead the team's Marine capabilities.

Amongst others, Martin holds a degree in Risk Management and is a Member of the Registered Insurance Advisors in The Netherlands.


Ronald Harms – Director

Ronald has over 30 years‘ expertise in the insurance broking industry. Prior to joining Howden, he was Director of Marine for Aon Risk Solutions. Ronald's focus is on logistics and marine liabilities as well as cargo insurances.


Willem Spoorendonk – Director, Non-Marine

Willem joined Howden in October 2013 to focus on providing non-marine insurance solutions for a wide range of national and international (direct) clients.

Willem started his career in 1974 as a Property Underwriter at Norwich Union and has since become a specialist in General Liabilities.  In 1996 he made the switch to an Insurance Broker.


Gerard Schouten – Senior Claims Specialist

Gerard has over 35 years’ experience in the Marine Insurance industry managing claims, initially as a Hull & Machinery underwriter whilst as from 1987 as an insurance broker, also focusing on cargo and  cargo-liability; road hauliers, terminal perators, warehousing and land-based equipment.


Jacco De Jonge– Senior Claims Handler

Jacco has over 25 years' claims management experience in the insurance industry. He has a particular focus on inland and ocean hull, land-based equipment, builder’s risk and pleasure crafts.


Vijay Mangroe -  Specialist Marine Broker

Vijay has over 12 years' marine insurance experience and now focus on providing marine insurance solutions for a wide range of national and international (direct) clients.

Vijay started his career in 2001 as a Marine Hull Underwriter at HDI-Gerling Verzekeringen specialising in the field of land-based equipment, towage risks, ocean hull, inland hull, builder’s risk and pleasure crafts.  In 2008 he made the switch to an Insurance Broker and joined Concordia de Keizer as a Marine Specialist.

Vijay holds an MBA degree in Marketing and Corporate Communications and a variety of Insurance Certificates.


Justin Pronk -  Specialist CAR / Engineering

Justin is a specialist in engineering, as well as Renewables, CAR and machinery breakdown.