A corporation whose shares are held by a single shareholder or a closely-knit group of shareholders (such as a family) is known as a close corporation. The shares of stock are not traded publicly. Many of these types of corporations are small firms that in the past would have been operated as a sole proprietorship or partnership, but have been incorporated in order to obtain the advantages of limited liability or a tax benefit or both.
A buy-sell agreement is an agreement between the owners (shareholders) of a firm, defining their mutual obligations, privileges, protections, and rights. This form is a generic example that may be referred to when preparing such a form for your particular state. It is for illustrative purposes only. Local laws should be consulted to determine any specific requirements for such a form in a particular jurisdiction.