No. A penalty clause in an employment contract that operates one-sidedly against the employee is invalid. Court of Cassation practice requires reciprocity before a penalty binds the employee: the employer has to be subject to an equivalent sanction on the same obligation. The Turkish Code of Obligations (No. 6098) also allows a judge to reduce a penalty found to be excessive, so a disproportionate figure is not applied as written.
So rather than attaching an automatic penalty to “every breach”, draft selectively, around the interest you are actually protecting — confidentiality, non-competition, training costs. Legitimate structures survive when they are proportionate: repayment of training costs stands a far better chance where it tapers with the time served than where it falls due in full on the first day. And a non-compete penalty has to be limited in duration, in territory and in subject matter.
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