help with a herman miller fiberglass stamp??  

Hi,
I have recently acquired 2 fibreglass shell eames chairs. The overall look and condition seems to stack up to an original chair, however, the stamps seem to differ from what I have seen before. They both carry the herman miller logo, but neither have 'Herman Miller' embossed under the logo. 1 has a 'V' stamp next to the logo and the other has an 'S'. All the others I have seen carry both the logo and the text embossed underneath it.
Is it possible these are still genuine? Or did they never produce this format.
Any thoughts would be hugely appreciated.
Thanks