Is Your Trademark Confusingly Similar to Your Competitor?

Relatedness of Goods and/or Services

Even if two marks are found to be confusingly similar, a likelihood of confusion will exist only if the goods and/or services upon which or in connection with the marks are used are, in fact, related. Whether the goods and/or services are related is determined by considering the commercial relationship between the goods and/or services identified in the application with those identified in the registration or earlier-filed application. To find relatedness between goods and/or services, the goods and/or services do not have to be identical. It is sufficient that they are related in such a manner that consumers are likely to assume (mistakenly) that they come from a common source. The issue is not whether the actual goods and/or services are likely to be confused but, rather, whether a likelihood of confusion would exist as to the source of the goods and/or services.

Source USPTO.GOV