A fictitious business name, also referred to as FBN, doing business as, DBA, dba, D/B/A, or trade name is a name other than your own legal name, or the official name of your corporation, LLC, or other business entity. To use such a fictitious business name in California, you must file with your local government, usually at the county level and then publish a notice of this fact in a local newspaper of general cirulcation to put the public on notice of your assumed name. One person or company may have multiple fictitious business names.
A fictitious business name is not the same thing as a trademark or service mark. Firstly, because a DBA is only searched and registered on a local, rather than state or federal, level, and secondly, because registering a DBA does not in itself grant any trademark rights. A fictitious business name is generally not a subtitute for trademark registration.
FBN is sometimes mispelled "ficticious business name".