Searching for a legal business name may require several different methods. Depending on the type of business, the legal name may either be the full name of the owner (for sole proprietors), last name of the business partners (partnerships) or business name registered with a state government (limited liability corporations (LLCs) and corporations). The legal business name may be different from name the business is known as, or the "doing business as" name. Finding the DBA or fictitious name first may lead you to finding the legal business name.

Complete a Internet search of a business name by typing the business name into a major search engine and reviewing the results. Also, complete a search of website domain names. Review the company’s own website. It may list its legal, full business name in attached legal documents, press releases, company history or in small font on the bottom of the home page.

Check the U.S. Patent and Trademark Office’s national trademark database at uspto.gov. Enter the business name into the search function and review the results. This may produce the legal business name, the DBA and even trademark product name, logos and phrases.

Locate the company's employee identification number to search government records. Every company that has paid staff must obtain an employee identification number and file taxes through the Internal Revenue Service (IRS) in the legal business name. The IRS, U.S. Securities and Exchange Commission (SEC) or other government agencies may be able to provide additional documents leading to the company’s legal business name.

Search state databases for business names. Most states require that businesses register their names with the Secretary of State or County Clerk’s office. These states often have an electronic database where you can input the business name and complete a search. If not, you can contact the appropriate office and speak to staff to determine existing business names.