I've had this happen several times recently. I kill a dragon, and it just lies there. None of the visual effects for a dragon soul absorption, nor the soul itself. Anyone else having this problem?

Yes it's a known problem. It's no big deal it just svcks when you need a dragon soul. Now that I'm level 70 I can careless. I think I have around 50+ souls so it's not anything to me. Next patch should fix it. Hopefully

Happened to me about five times now. I can't prove it but I think it happens when they die on a slope and slide. In such cases I feel justified in granting myself the soul via console

player.setav dragonsouls 

Maybe there's a distance check that gets screwed up if the dragon is still moving? In other words, there is a radius that you have to be within in order to gain the soul, and if the dragon is still moving enough/in a certain way while this occurs, it spits out an int/floating point number that is out of that radius, such as a negative one.

It seems to happen to me when I have killed a scripted dragon in the same area previously and then a random one spawns. Patch notes claim it was fixed but it's not fixed.

In my case at least it's nothing to do with distance because I am right there.

Well that's the thing with code. Even if, visually, you might be right on top of a dragon, there may be an error in the coding that spits back a non positive number. As an example:

if radius<0:
return False
elif(else if) radius<=100:
return True

A calculation error could really screw that up.The other possibility is that the dragons giving you souls are actually unique dragons with generic names. That said, these "unique" dragons have already died once, thus you do not get a second soul from them.

Yea that happen to me too it svcks but another dragon will come round and you can get that soul.

This has happened to me as well, however I realized it only happens with quests or bounty dragons that I have previously killed. They respawn to complete the quest yet are scripted to not provide another soul

Exactly.

Randomly encountered dragons are freshly generated from a leveled list each time one is triggered, so will always have a soul, as will dragons encountered on an initial trip to a word wall. The latter, however, are unique, so when the cell respawns a generic version is used instead that doesn't have one.

I suspect that the substitution is meant to stop the farming of souls, although it's basically wasted effort since you'll end up with far more of them than you need anyway. Of course, there's also a lore-based reason for it, since you can only absorb a given soul once, but I have a feeling that's not why it was done.

Hah, if they bother to respawn. I've got a bug where the dragon didn't want to spawn for me.