Serial Number on Gibson A-50

[RickRinehart]

The only number I can find is printed inside looking through the treble side F-hole. I see 963F and a 3 (the 3 is handwritten). There is no paper label. What does this number mean?
Thanks

[f5loar]

This is the FON (factory order no.) and it is the 3rd one made in batch no. 963 in 1940. Should have the prewar Gibson logo in script at the top in white paint or pearl. They did not use paper label on the lower end models.

[RickRinehart]

Thanks f5loar for the explanation. All the references I saw indicated it should be a much longer number. I was wondering what I had. I really like this mandolin.

[f5loar]

not on the lower end models. They only had FON and no serial nos.
The FON is either 3 or 4 digits plus the ranking number and in your case the F is for 1940.