I believe that the knife came from the factory with smooth bone handles. It came in its original factory packaging and shows no signs of being reworked.
All of the other LB5's that I have with wood handles, have pins that are flush with the wood. As you can see in the photos, 2 of the 3 pins on this knife have heads.
I was thinking that the knife was some sort of SFO but I've never seen another one
Keith