The South Dakota Letter of Consent To Use Similar Name is a legal document obtained from the South Dakota Secretary of State that permits an individual or entity to use a similar name to an existing business name or entity name already registered with the state. This document is required by the South Dakota Business Corporation Act and the South Dakota Nonprofit Corporation Act to ensure that the new name is not too similar to an existing name. The South Dakota Letter of Consent To Use Similar Name must be signed by the registered owner of the existing name, and must be filed with the Secretary of State's office. There are two types of South Dakota Letters of Consent To Use Similar Name: one for corporations, and one for limited liability companies (LCS).