It is not a genuine error. It is a magicians trick. My wife brought one of these home that she got from one of her students. The seal is printed at the same time as the green seal and serial numbers. For the black seal to be shifted, these elements would also have to be shifted.
What I do not understand, is that all of the numbers and seal in black are printed at the same time. Look very close at the area where the seal should be. If the area doesn't look right, then it's doctored. No value. What's the back look like? -O)
this has been doctored. You can see the outline of the seal above the serial number. It was removed with some sort of bleaching agent and a false seal was printed in the wrong spot. Richard
It isn't true that a black seal can't be printed askew while the bank numbers are correctly positioned; the machinery can malfunction to allow it. However in this case, it appears to be doctored. Look at the black seal under magnification, it may appear to be made of small dots, the result of being printed by an inkjet