In the United States, a trademark can be claimed by either (1) successfully filing an application with the United States Patent and Trademark Office or (2) acquiring a trademark through common law rights. Because you stated that SensoBright did not procure protection through the filing route, my response is going to cover common law trademark rights.
Your competitor could have acquired common law trademark property rights by using the trademark in commerce. In the U.S., the first firm that uses the mark in commerce claims its rights and the privilege to prevent others from using the mark. SensoBright can maintain these rights, though, only by using the mark on a regular basis as part of its business activities and can only enforce its trademark rights in jurisdictions where the trademark has been used and is likely to expand. All hope is not lost, though, a necessary predicate for acquiring a trademark is placing others on notice that the firm plans to use the symbol. The usual way to do this is to use the term ‘TM’ after the trademark. If SensoBright has not done this, I would recommend that you go ahead with your firm’s activities. In the alternative, if SensoBright has gone through the proper procedures for establishing its common law trademark, remember that you can still use your mark in American markets where SensoBright does not do business.
These are rough guidelines on common law trademark rights. If you message me and provide me with more information, I can provide you with detailed advice. I hope this helps.
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