Legal Question in Business Law in California

Re: Business names

Filing a fictitious business name statement provides limited, at best, protection for the use of a trade name. More powerful protection comes from registering a state and/or federal trademark. However, if you are the first user of the name and can show use in trade, such as labeled product, advertising, your store front, etc. using the name, you may have established some common-law rights that you could enforce. Your best bet is to have a local lawyer who does business stuff write a cease-and-desist kind of letter to the other firm, and see what the response is. Then consider registering your name as a trademark. Possibility of confusion by customers is, as you recognize, the big legal issue and to win in a suit you would have to show that, plus the superiority of your right to use the name over the other guy.