In Carter, this logo is described as one used on export bayonets.
I have only found it on two long KS98s, one of which I had found on e-ban. I used to own both, but could find no one who thought this mark was special in any way and finally sold my poorer copy to Tom Witmann for a ridiculously low price.
I would guess that the time period for this mark was the same as for the equivalent double oval.
There was a thread here or on WAF where Tom Johnson talks about how these various maker marks were all used concurrently based upon the produciton chief's whim, so trying to date them beyond the simplistic age sequence (back to back, single oval, double oval, seated squirrel, over shoulder squirrel) may be futile.
John
