i gues he done them hisself,
nway what can i maybe tell you what i like on ur old sigs and one this one ( i mean what i thinks is different):
in your old sigs you added alot of contrast and alot of detailed work , in your cuncurrently sig you have even recolored the stock and colored it one some parts to make the mood into the sig.
your new sig in months is simple with one color overlayed and doesnt truelly explain what the person is trying to explain, i mean there´s just a person with hold his hands far away.. is he happy? is he sad? how does he feel? is he trying to show something?
you used to many light colors... you could easily now take one of your brushes.. make it black /darkorange and set on multiply and a opcatiy of 30-45% ... maybe even less..
i liked your work always and i like to see more of it.