Is it possible to trademark a brand name if it's similar to one that exists?

In the United States, the key is determining whether there is a likelihood of confusion. In other words, are consumers likely to believe that the goods are made by the same person. Similarity of the marks is just one factor. Another important factor is the relatedness of the goods. If the goods are wine, for example, and you want to use a similar mark on a wine, then there would be a greater likelihood of confusion. If, however, the goods are orthopedic shoe inserts, then the likelihood of confusion is greatly reduced because few people would think that a winery made orthotics.

Registered trademark protection in Vietnam

There is an exception for famous marks because they are so strong. For example, if you saw a bar of APPLE soap, you might not think that APPLE has gone into the soap business, but you might think of Apple computers or products. That is called “trademark dilution” because it is likely to diminish the value of the APPLE trademark. In that case, likelihood of confusion has nothing to do with the analysis.

Source: Quora 

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