I looked into this recently because of a rep of mine that was leaving for opposition pastures.
The advice I was given was this.
Let's say the business is a car dealership. The rep is an experienced rep, comes into the business with his experience and knowledge, his own contacts etc, and decides to leave. There is little chance of the restraint being enforced.
However, the dealership hires a photocopy salesman. They train him, give him the benefit of their experience, help him build up a network of contacts, and then he leaves. In this case, you have a strong case to enforce a restraint. You need to prove that he has gained this insight at the expense of your company, and that by him going to the opposition, his gained knowledge will be detrimental to the business he is leaving.
If the guy can prove that he has no other way of making a living (in my case the rep could have gone to work for another engineering business that was not opposition to us) and that working for the current company is no longer feasible, then it is difficult to get the restraint enforced.
Hope this helps.
This is not qualified advice - it is what I was told by a labour consultant.
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