A company is said to "do business as" when the name under which it does business differs from its legal registered name. Some states require you to submit a dba or fictitious company name to protect consumers doing business with the company.

If you are a sole proprietorship or a partnership, you have the option to choose a company name or a dba ("doing business as"). If you wish to do business under a name other than your real name (eg Carol Axelrod does business as "Darling Donut Shoppe"), you may need to register your county, city or state under a fictitious name. (Note: A fictitious company name may not contain the words "Corporation," "Inc.," "Incorporation," or "Corp." unless it is a legal entity registered with the Secretary of State.)