Hook up with DJ -he broke it down and knows what's up :op (just teasing, but he did have an excellent point).
If you are concerned with "official", I assume you date one man at a time toward a meaningful relationship/marriage -(most these days don't realize a relationship should mean something).... so if a man is dating several women at once, he is not sensitive to your (or their) feelings, and is probably not looking for a commitment. If relationships are built on trust, (his)sensitivity to the feelings of another(yours) is essential.
Dating toward marriage is NOT the norm these days, so be careful and be clear.