Josh Gerben wrote an article for Security Sales & Integration aimed toward security professionals that discusses what they need to consider regarding trademarks.  Here are some excerpts from the article:

“The reasoning behind [filing for your business name] is straightforward: Obtaining a trademark registration on your name gives you the broadest level of protection. Obtaining protection on other brand elements — like your logo for example, offers protection in a much narrower scope.”

“If [a competitior with the same name] choose not to change their name and you decide to sue them based on a theory of common law trademark infringement, trying to prove your rights to the name will be far more difficult and expensive than the cost of applying for a federal trademark registration.”

 

Source: Gerben, J.  “Trademarks 101: What Is a Trademark and Why Your Business Can’t Live Without It”.  SecuritySales.com  February 22 2018.