a) Both of you ( the "parties" concerned) need to have a "Letter of Offer" of the position to you in place, setting out all the terms and conditions etc. It protects both parties and you both sign. This includes matters relating to confidentiality, anything related to expected conduct, and the method of judging your performance.
b) You should ask that the condition in the Letter of Offer that sets out the "structure" of this "bonus", should say words to the effect
1) that if you terminate for any reason before 3 years you pay it back and
2) that if they terminate you before 3 years because of a disciplinary matter or non performance then you pay it back and
3) that if they are terminating you for a reason other than a disciplinary or performance related matter (ie eg the position doesnt work out, or they re structure, whatever etc)....then you dont have to pay it back.
4) that if the parties dont agree the reason for termination and you want to argue, that the matter goes to a mediator.
etc etc etc. *
Cant be fairer than that, its all reasonable and is not unheard of.
Hope this helps.
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