lutters cue?

[knzn]

After eating lunch the other day, a friend of mine pulled a single blade pocket knife with wood handles out of his pocket and began cleaning his finger nails.
Being the nosey kind of guy that I am I asked to see it. The tang on one side was stamped "lutters cue." The other side was stamped Solingen Germany.
Anyone ever heard of this before?
Or maybe even a web site that has them?
thanks