Every researcher with an employment contract with a university of applied sciences institution follows the rules laid down in the Dutch Copyright Act and in the collective labour agreement for universities of applied sciences . Article 7 of the Dutch Copyright Act and Article E-7 of the collective labour agreement for for universities of applied sciences are clear: the rights belong to the employer (university of applied sciences) if the resources were created during the performance of the employment contract.
The university, too, according to the Copyright Act and the collective labour agreement, is in principle entitled to copyright on the work and creations of its employees. However, how this is handled in practice differs from one university institution to another. At some universities, in practice, the author is considered the copyright holder. At other universities, the employer (the university in question) is seen as the rights holder. Check with the contact person at your own institution.