Midden-Nederland District Court, 17 September 2025, ECLI:NL:RBMNE:2025:4897
Midden-Nederland District Court recently ruled on the annulment of an addendum to an employment contract on the ground of mistake. The central question was whether an employee had breached her duty to disclose by not reporting her mental health symptoms when agreeing to an increase in her working hours.
Facts
Newstyle operates gyms in the Utrecht and Leiden area. On 1 February 2025, Newstyle opened a branch at the location of the former David Lloyd gym. The employee, previously employed by David Lloyd, was offered an employment contract by Newstyle for 12 hours a week and started working for Newstyle on 3 March 2025.
After a few months, the employee indicated she wanted to work more hours. On 18 May 2025, she signed an addendum to her employment contract increasing her working hours from 12 to 31 hours a week, effective 1 June 2025.
On 22 May 2025, four days after signing the addendum, the employee reported sick to her manager. In the following days, she indicated she was suffering from anxiety and panic attacks. She reported having used antidepressants for four years and having experienced an increase in these symptoms in the weeks before her sick leave, symptoms she had also struggled with in the past.
On 18 July 2025, Newstyle annulled the addendum to the employment contract on the ground of mistake. According to Newstyle, it had emerged that, at the time of agreeing to the amended employment contract, the employee knew, or should have known, that she was medically unable, or would be unable, to carry out the agreed increase in working hours and duties.
Ruling of the subdistrict court
The subdistrict court first noted that the possibility of extrajudicial annulment on the ground of mistake is not excluded in employment law. The protection employment law offers an employee must still be respected, but dismissal law does not protect an employee who used deceit or mistake when entering into the employment contract.
An employment contract can be validly annulled out of court on the ground of mistake where, at the time of signing, an employee possessed information about their health that they should have disclosed to the employer.
Such information exists where an employee, when concluding the employment contract, actually knew their state of health was such that it would seriously and lastingly hinder them in carrying out the agreed work.
The subdistrict court ruled that, in these summary proceedings, it had not been shown to be plausible that Newstyle knew of the employee’s psychological symptoms at the time the employment began or when the addendum was signed.
The employee should have understood that her psychological vulnerability was relevant to whether she could structurally take on more duties and hours. By not disclosing her symptoms when signing the addendum, the employee breached her duty to disclose.
The extrajudicial annulment of the addendum therefore does not conflict with the closed system of dismissal law.
Conclusion
This ruling clarifies under what circumstances an employer can extrajudicially annul part of an employment contract where an employee has concealed relevant medical information.
As an employer, are you dealing with an employee who concealed relevant facts or circumstances when entering into the employment contract? Our employment lawyers are ready to help.
Click here for the full ruling (in Dutch).
