LegalZoom also talks about unregistered trademarks (https://en.wikipedia.org/wiki/Unregistered_trademark https://en.wikipedia.org/wiki/Unregistered_trademark) a

LegalZoom also talks about unregistered trademarks (https://en.wikipedia.org/wiki/Unregistered_trademark https://en.wikipedia.org/wiki/Unregistered_trademark) and the comparison with registered trademarks at http://info.legalzoom.com/registered-vs-unregistered-trademark-21089.html http://info.legalzoom.com/registered-vs-unregistered-tradema... and http://info.legalzoom.com/report-use-unregistered-trademark-22578.html http://info.legalzoom.com/report-use-unregistered-trademark-... . You first send a cease and desist letter. > If the infringing party does not comply with your cease and desist letter, you may protect your unregistered mark by filing a lawsuit for trademark infringement in your state court. Your lawsuit will need to notify the court how long you've been using the mark and how the other party is infringing on your rights. Because an unregistered trademark is only granted protection within a limited geographic area, any infringing use outside of this geographic area will not be enforceable. A third party who files for federal registration of your unregistered mark, even after you've been using it, may be granted the right to use that mark in all geographic areas other than the limited area where your common law rights exist.