SGC slab question
 

I recently bought a nice looking card in an SGC slab and when looking at it, it seems that one side of the slab sticks out just a tiny bit more than on my other SGC slabs (the back half of this one seems to have an edge on that side just a bit beyond what is typical). This slab in question is of the new variety, which I compared to other new ones. It shows no signs of being tampered with and I tried to open the case by hand to see if it came apart easily, which it did not.
Anybody else encounter a similar slab? I suppose it could be some type of higher level tampering, but I think it may be more likely that the slab itself just has a back half that's a tiny bit wider on that side.
Thanks.