Whose name shows up on a certified letter post card when you are being sued?

I checked my mail today and received a postcard from the post office saying that I have a large certified mail envelope from one of my roommates (I've been feuding with both of them over thousands of dollars they owe me for rent and security deposits and even had to sue them over it.) I want to know if a person is being sued and they miss receiving the certified letter, whose name shows up on the card, the person suing or the court??