Early Boker question

[beresman]

Hello, all! I just took delivery of this knife, and looking at the tang stamp chart available here, I have a question. The knife in question is marked (on both blades) "H.Bokers Improved Cutlery". The smaller blade has an apostrophe in "Boker's", the larger does not--and the spacing of the letters would indicated that there never was. There is no tree logo on the opposite side of either blade.

The question has to do with the notation in the first two entries on the chart, "No tree on reverse--very rare". The third entry shows the tree logo within an oval. Does this imply that every Boker knife after that would have included the tree logo? Mine obviously does not; it shows no signs of being modified. Who can tell me the story here? And thanks in advance!