関係がある

関係がある is used to express that there is some connection, involvement, or relevance between two things. It does not specify the strength of the link; it can be formal, practical, or casual. Use は/とは to indicate the topic or contrast when needed. Typical contexts include discussing professional or personal ties, indirect influence, or relevance to a matter. For example, you can say that you have a relationship with a company (会社とは関係がある), or that a certain issue has nothing to do with you (その件とは関係がない). When the two entities are clearly distinct or you want to deny involvement, use ない form. Remember that 関係がある focuses on existence of a link, not on emotional closeness.