Is It Okay To Write A Stamp Number On A Stamp?

You have a good eye finches.

The writing in German Feld 50 Vogelschwarm translates
as " Field 50 Flock of Birds".

The 650 I believe indicates DM 6.50 which was probably the catalogue
value at the time the collector scribbled on it.

Here is a close up.



It's possible that I wouldn't have noticed this plate flaw if
he hadn't scribbled on the selvage, so I guess it wasn't such
a bad thing after all.

BTW does anyone have a recent Michel Deutschland Specialized,
I'm curious if it's listed & what the value is.

Wow! Very interesting comments. I think the last ones I wrote on (that I can determine anyway) were cancelled 1982 - one of each catalog number of duplicates. And I think I now remember why.I had sorted and placed the cancelled dups into glassine envelopes but didn't have anything to label the glassines at the time. So I lightly wrote on the back of one stamp so I would know the cat number. Of course, I never got around to labeling the envelopes. Result: If I had one dup, it had the number penciled on the reverse. If I had multiples, only one had the number on the back.

I was removing some inexpensive used stamps from an album and found that each family member had written their name on the back of the stamp they claimed as their own. So some stamps said "Dad", some stamps said "Mom", some stamps said "Doug" and I can't remember how many others were involved.

I think I was a little miffed that their names were in pen, but on the other hand, I did get a warm fuzzy feeling when I realized that they shared a wholesome activity together.