Types of Material Changes
There are many types of changes to be made. It must be separately determined whether each change constitutes a material change, depending on the situation. However, some of the main types of material changes are as follows:
- Nature of the Work
- Working Hours
Procedure to Apply Material Changes
As briefly mentioned above, Article 22 of the Law states that working conditions arising out of the employment agreement, internal regulations or workplace practices may be changed only if the employees are notified in writing prior to the change.
Furthermore, employees of the company should be notified in writing and asked to respond within 6 business days as to whether or not they object to the changes. If they do not respond, employees will be deemed not to have accepted such alterations.
The Court of Appeal has also stated that, while employees can give their written consent to the employer, the parties may also prepare and sign a new employment agreement. Such a new agreement will also be regarded as the written consent of the employee.
 9th Chamber of the Court of Appeal, file numbered 2017/12121 E., 2019/11461 K. and dated 20.05.2019
If the Employee Objects to Material Changes
Changes which are not accepted by the employees in written form within 6 business days following the written notification of the employer shall not bind the employee. Therefore, the employee cannot be forced to act in accordance with the changes that have been made.
For example, if the employer decides to decrease the salaries to the detriment of employees and the employees do not give their written consent to this change, the employer cannot pay decreased/changed salaries to employees.
It must also be stated that, if the changes are made to the detriment of employees without their written consent, employees will have the right to immediately terminate the employment agreement and claim severance payment.
However; if an employee does accept the material change, the employer will have the right to terminate the employment agreement at the end of the statutory notice period by making severance payments and paying other receivables to the employee.
The Court of Appeal has stated that if an employee does accept the material change, this does not provide any grounds for immediate rightful termination by the employer. As stated above, the employee must wait until the end of the notice period and must make a severance payment.
Furthermore, any provision within the employment agreement which allows the employer to solely apply material changes shall be deemed to be invalid
 22nd Chamber of the Court of Appeal, file numbered 2017/22056 E., 2019/10532 K. and dated 14.05.2019