One's ability to register a trademark can depend on whether the trademark to be registered creates a "likelihood of confusion" with a pre-existing trademark.
Whether there is a likelihood of confusion requires an analysis of several factors. Those factors include similarity of the marks, similarity of the goods/services, similarity of the trade channels, sales conditions and purchaser sophistication. The greater the similarity, the more likely the confusion.
Nevertheless, similarity of the marks is often of greater importance than the other factors. Importantly, the factor is based on "similarity", not whether the marks are identical.
For example, a trademark applicant tried to register the mark FOCUSVISION for market research software. A trademark owner opposed the registration because it owned trademark registrations for FOCUS which related to database management software.
The Federal Circuit explained that the similarity of the marks factor concerns the "similarity or dis-similarity of the marks in their entireties as to appearance, sound, connotation and commercial impression." Yet, it is proper that "more or less weight [be] given to a particular feature of the mark."
In this case, it was proper to give more weight to the first half of the mark - FOCUS, as opposed to the second half - VISION. Therefore, the applicant's mark incorporated the registered mark (FOCUS) in its entirety. Also, FOCUS is the term consumers "would consider in perceiving" the applicant's mark.
Furthermore, applicant's addition of VISION did not change the meaning of FOCUS.
In determining whether one can register a trademark, it is important to determine what part of the mark may be important or focused on by consumers. That important part can then be compared with other marks for conflicts.