Flies officially become lures under five conditions:
1. More than four pairs of treble hooks.
2. Their weight makes them impossible to cast even with a #12 weight rod and matching Clouser line
3. They cause invading BASS anglers to back off their boats when you fling one in their direction.
4. Every fish in a two mile radius flees when the fly/lure hits the water
5. When every single member of FAOL agrees that it's a lure
Hope this helps clarify the distinction. 8T