External PhD candidates conduct doctoral research without being employed by a university. They conduct their research without remuneration and in their own time as a hobby or on behalf of a company. Anyone who wants to become an external PhD candidate should contact a potential supervisor themselves. Information for external PhD candidates and their associated rights and obligations can be found on the websites of the universities.
An external PhD candidate is someone who carries out their PhD research without being appointed at a university. Therefore, external PhD candidates are responsible for financing their own PhD trajectory. Research from the Rathenau Institute estimates that about half of the PhD candidates in the Netherlands do not have an appointment with the PhD as their main objective. So, half of the PhD candidates in the Netherlands are buitenpromovendi. Based on the number of employee PhD candidates in the Netherlands (based on UNL figures from 2018) , there are an estimated 9000 externally funded PhD candidates in the Netherlands.
Universities are free to set their policies regarding external PhD candidates. Many research schools use this freedom judiciously, but there are also abuses. For example, the VPRO program Argos showed that Tilburg University used shady constructions that were mainly aimed at quickly obtaining the PhD bonus. PNN is strongly opposed to such practices.
Currently, PNN is working on mapping the situation regarding external PhD candidates to determine whether further action is necessary. The aforementioned Rathenau research shows that external PhD candidates expect more delay than employee PhD candidates. Additionally, external PhD candidates are less well integrated into the university and less positive about their supervision than employee PhD candidates.
The definition of external PhD candidates used above is common, but also causes confusion. The differences between outside PhD candidates are significant. To better account for these differences, the UNL UNL introduced a much stricter definition in 2019. In this definition, the name external PhD candidate is reserved for a PhD candidate who finances their own PhD from their own resources. PhD candidates who receive a scholarship (from their own university or another institution) are scholarship PhD candidates. PhD candidates who have external financing or who are doing their PhD during their employment are externally funded PhD candidates. If the latter happens at the university where the PhD is also taking place, it is referred to as an employee who is doing a PhD.
The benefits for the university per externally funded promotion are the same as for an employee-funded promotion. The promotion bonus that a university receives from the government for each completed promotion does not distinguish based on funding.
The costs for the university are limited to supervision and access to university facilities. Each university can determine the conditions under which they admit external PhD candidates. There is no overview of the various regulations for external PhD candidates, but it is clear that the differences between universities are significant. Even within a university, the rules vary per research school. Not only does the enrollment fee vary from zero to thousands of euros, but also the facilities offered, the intensity of supervision, and the number of years allowed for a PhD trajectory.