It's an unusual miscut.
There are a few causes with the same end result.
Debris in the stack of sheets
damage to the stack of sheets
Damage to the sacrificial strip the blade goes into after finishing the cut.
All three will bend the stack and cause an odd cut like that. Or a curved cut.
And it's not just C55s Here's a T206 with the same sort of cut on the top and bottom edges. Also slight creases/bends where the sheet was bent, but those don't scan well.
Steve B
