Hamer van Hussen Groenendijk is the result of the merger in 2019 of two Rotterdam-based marine surveyors, J. Hamer & H. van Hussen and Expertisebureau Groenendijk. Both companies were founded in 1969 and have been operating successfully ever since.

Hamer & van Hussen was established on 1 February 1969 by Jouke Hamer and Hans van Hussen. A few months later, on 16 May 1969, Cees Groenendijk senior founded Expertisebureau Groenendijk..

Both companies were typical family businesses, with several generations employed, supported by good teams of loyal employees. The son of Cees Groenendijk Sr, Kees Groenendijk Jr, joined Expertisebureau Groenendijk at the end of the 1970s and later became director. Wieger Hamer joined Hamer & van Hussen in 1991 and took over the company about a decade later. In 2010, Ben Groenendijk joined Groenendijk and took over the office a few years later when his father died at a young age.

The two companies had more in common than just location, age and family history; both were relatively small but specialised in cargo claims. Both had built up a good reputation in their field over the years, and both worked mainly for underwriters and brokers active in the co-insurance market. Most importantly, the cultures and mentalities of the companies were very similar.

We later realised that our predecessors had been considering a possible merger for many years, but had never shared the idea with each other. When both companies existed 50 years, we decided to merge in 2019, on 1 February 2019.

Initially, each company continued to operate under its own well-established name. After 2.5 years we realised that the sum of both companies had made us both stronger. We therefore continued under the logical name: "Hamer van Hussen Groenendijk".