First neighbourhood-level study on the effects of the Purchase Protection Act wins Rotterdam Thesis Award 2026

The thesis of Hugo van den Belt focuses on Rotterdam and examines the consequences of the Purchase Protection Act in the city. Using an econometric analysis model, Hugo evaluated the law's impact on Rotterdam. The thesis takes a quantitative approach, drawing on publicly available data from the City of Rotterdam and Statistics Netherlands (CBS).

Investor activity declined

Previous research by the Land Registry (Kadaster) and Erasmus University Rotterdam had already shown that property buying activity was declining. Van den Belt now demonstrates what this means in the neighbourhoods themselves: more homes occupied by owner-occupiers and fewer vacant properties. However, housing prices remained unchanged. This is due to the immense pressure on the housing market: demand far exceeds supply, ensuring there is always a buyer willing to pay the asking price or more, whether an investor or an owner-occupier. In a city such as Rotterdam, with a severe housing shortage, making better use of the existing, often vacant, housing stock could prove just as beneficial to society as a whole as lower prices.

Hidden rental sector statistically uncovered 

By chance, the statistical method used in the research of Hugo revealed a large, unregistered rental sector that is invisible to the municipality. This unregulated market operates outside municipal oversight, leaving tenants vulnerable to risks such as illegal subletting, overcrowding, and rents far above the legal limits (issues that Rotterdam’s tenant advocacy teams and journalists have previously flagged). Gaining insight into the scale of this market is essential for effective enforcement and the protection of vulnerable tenants.

The jury report states that the thesis of Hugo excellently demonstrates the effects of the law in Rotterdam and highlights both its advantages and disadvantages. This is achieved through a well-applied methodology that showcases the student’s mastery of research techniques. The thesis is well-written, and its findings are rich, surprising, and highly relevant. Jury Chair Prof. Martijn van der Steen adds: ‘The policy recommendations in the thesis are clear and could assist policymakers in refining the legislation and deciding whether to continue the Purchase Protection Act. The jury is deeply impressed by the thesis.’

The thesis, titled “Investor restrictions and the housing market: an evaluation of the Purchase Protection Act (Wet Opkoopbescherming) in Rotterdam,” was written by Hugo van den Belt for his Master’s programme in Economics & Business: Economics of Markets and Organisations at Erasmus School of Economics, under the supervision of Dr Sacha Kapoor.

Two winners of the Rotterdam Thesis Award 2026

Due to the high quality and relevance of this year’s submissions, the jury made the exceptional decision to name two winners. The other winner is Stephanie Habets alumna of Erasmus School of Law (Criminology).

To encourage students to apply their academic knowledge for the benefit of Rotterdam, the Municipality of Rotterdam and Erasmus University Rotterdam established the Rotterdam Thesis Award. The jury, consisting of academics, municipal officials, and a city council member, evaluates submissions based on their relevance to Rotterdam and their scientific quality. The award includes a certificate, an artwork by a Rotterdam-based artist, and a cash prize of €1,500.