An excellent question and one which the Court of Appeal has had to consider in the recent case of M Tillman v Egon Zehnder Limited (July 2017).
It is well established that provisions that seek to restrict an employee’s activities following the termination of their employment are in restraint of trade and therefore unenforceable UNLESS they go no further than is reasonably necessary to protect an employer’s legitimate business interest.
However, it is imperative to ensure that careful consideration is given to the scope and duration of post termination restrictions and that they are carefully drafted so as to afford an employer with the protection it needs.
Read Alexandra Bonner's article (see the link below) for a discussion of the Court of Appeal's findings in the Egon Zehnder case in relation to (i) the need to ensure that restrictions are tightly drafted in terms of scope and (ii) in terms of the limited power of the courts themselves to exercise their right to “blue pencil” (delete/sever) wording included in a provision (which renders the covenant too wide but without which the restriction would be enforceable)
This case demonstrates that it is vital that restrictions are reviewed on a regular basis so as to ensure that they are and remain fit for purpose so that they can be enforced when it counts most.
This case clearly demonstrates that the Courts have, in fact, a very limited right to fix a restriction that is too wide by deleting a few words, rather it is incumbent on the employer to ensure that, at the time the restrictions are entered into, they are appropriate to the role and sufficiently narrow in scope and duration.