If the stamps are common, run of the mill
I would go for a collectors mark, "D"=duplicate?
He probably didn't realise stamps are only on loan to us
we never really own them, but for a short time.
Other marks can be traced to "expertisers" marks
and dealers as explained before.
There are "expertisers" web links available with
traceable icons.
A Belgian example:
Posted 09/22/2010 5:30 pm
