Enforceability turns on three questions, applied differently in every state.
Protectable interest. Trade secrets and confidential information, customer relationships and goodwill, and specialised training. Preventing ordinary competition is not a protectable interest, and a covenant that protects nothing beyond the employer’s preference not to compete fails.
Reasonableness. Duration, geographic scope and the scope of restricted activity, each assessed against the interest. Duration beyond a year is scrutinised in many states; geographic scope must relate to where the employee worked; and activity restrictions should be limited to the work the employee actually performed.
Consideration. Employment itself at hire in most states. For a covenant signed by an existing employee, continued employment suffices in some states and independent consideration is required in others — a bonus, a promotion, or access to new information.
Statutory restrictions. Several states prohibit non-competes below a wage threshold, for defined occupations, or entirely; require advance notice before an offer; and require a copy on request.
Blue pencilling and reformation. Some courts narrow an overbroad covenant; others strike it entirely. Which approach applies determines whether aggressive drafting is a strategy or a risk.