Graduate School of Social and Behavioural Sciences
According to the Leiden University PhD Regulations associate professors (UHD's) can be granted 'ius promovendi' , the right to award a PhD. You can request the ius from the Doctorate Board via the Dean.
The rule on this policy can be found in appendix E of the PhD Regulation.
The Doctorate Board will grant ius promovendi to you on the substantiated recommendation of the Dean of the faculty, who has established that you satisfy the criteria and has consulted with a full professor in the relevant discipline.
You will usually only be eligible for ius promovendi if you have supervised at least three PhD candidates to a successful PhD defence at a Dutch university or in similar supervisory pathways at non-Dutch universities, and have independently acquired the funds that financed the PhD candidates or have personally recruited the self-funded or external PhD candidates.