Common units are a security that represents ownership in a Limited Liability Company (LLC). Holders of common units, known as Members, can usually exercise control by electing Managers and voting on corporate policy. Each LLC has its own Operating Agreement that explains the rights of Members.

Members holding common units are usually on the bottom of the priority ladder for ownership structure; in the event of liquidation, Members holding common units have rights to a company's assets only after any bondholders, Members holding preferred units and other debtholders are paid in full.