Here's a photo from Rib 101:
Yes, whether Back/Loin/Spare whatever, there's a membrane...UNLESS someone already took it off. It does happen. It won't be for a while, but when I update Rib 101, I'll take some better photos.
It's best to start at one end or the other. Lots of techniques, but for me, I just use a paper towel. Pry up part of the membrane and SLOW peel it back. You want to try to take it all off in one piece. With practice you can. If it starts to slip, stop and try to pry up the split and pull it all off.