In the United States, non-compete agreements vary from state to state. Depending on state and local laws, the restrictions set by an employer, and other factors, determines if a non-compete agreement is legal and binding.
Many states have laws in place that protect the employer when it comes to a former employee accepting a new job with a company that may be seen as competition. This is also true if a former employee leaves a company and starts a business nearby that could be viewed as competition, and a conflict of interest. There are restrictions in place for the employee though, which in many states limits the period of time an employee can be held from opening a business nearby that may compete, or working for a company that may be similar to the employees previous job. Restrictions are sometimes only put on specific employees in managerial roles, or executives that may take a job with a new company. The reason for this being that employees that hold jobs of high importance or have spent a long period of time with a business, may have gained knowledge or even acquired skills in the workplace that could be beneficial to another company. These restrictions are not placed on other types of employees as often.
In many states, including California, non-compete agreements are not legal. California law says that citizens are not to be restrained of any sort of legal profession, business or trade and that any contract saying so is void. There