Four Reasons EMC Was First To Use A Trademark And Still Lost Its Case; Forbes, April 19, 2017

Jess Collen, Forbes; 

Four Reasons EMC Was First To Use A Trademark And Still Lost Its Case

"Do you get superior rights to use a trademark when you are the first to file for registration with the United States Patent and Trademark Office?

Not necessarily. A lot of companies know this already. The earliest date of first use usually prevails, even over a federal trademark registration. Sometimes, the question of “who did what, and when?” is difficult to sort out. To earn trademark rights, you must use the mark in a way that creates a sufficient association between your trademark, and your product, in the minds of the purchasing public. Not all use is created equal."