First, I would ask myself if there have been any other events in the residence in which you live? Anything that might have you look back and wonder if you might have looked at it more closely?
Sometimes these odd events seem associated with the residence, although I am no expert. I can only take you and your partner at your word until I know otherwise. Of course, there is the possibility that the scratches were already there and he wasn't 'aware' of them until he woke up 'suddenly', as it happened, after they got irritated somehow during the night. Who can say, with no picture here to look at?
If you have a photo, you can get some opinions on what made the scratches. You can also photograph the scratches as they heal to notice if there is anything else unusual about them. Even a doctor's opinion? The marks were bleeding as you say, so that would concern me a bit if I didn't know the origin of the scratches.
I am sorry to hear that you had such a frightening time. If you are being disturbed by some kind of entity, there are various ways to approach it. If you are purely curious, why not try a little evp recording? Otherwise, because this was a 'violent' occurrence, I won't advise you, others being more skilled than me, perhaps.
But see you and your partner surrounded by a white light of protection, or golden light is also one I use. Both of you can use this light to protect you and we can also send you this in the healing forum if you like.
I had a scare the other day too. But it was a false alarm. The table at which I regularly sit is ridiculously close to my front door. I like telling stories, so ignore me if this doesn't seem pertinent.
I was sitting there reading a Charlie Brown comic book, mostly about Snoopy the dog, and laughing. I had been in the doldrums for a while, the winter blahs, and this cheered me up. So, I'm in mid-laugh, and my doorknob starts jiggling really hard, and sounds sincerely like someone is breaking in. This goes on and on, and I jump up like lightning, feeling my adrenaline rushing (did I mention it was peaceful and quiet and evening time?). I peered out of the viewhole in the upper door, and saw a man standing there, who quickly left. I thought I was going to have a heart attack.
Later, I left to do something, maybe the next morning, I don't remember. I picked up the pizza flyer off the doorknob, where a rubber band held it in place.
My God, how hard is it to put a pizza place advertisement on my doorknob without scaring the living daylights out of me?
Guess I'm just saying, could be anything, anything at all.