As a retired lineman for BCTel/Telus, I can confirm that the fiber cables contain zero percent copper. The cables are identified at every pole with a tag that says "Fiber Optic Cable". These thieves either can't read or are in such a hurry that they choose not to read the tags. We hardly ever had to repair sabotaged cables, it mostly tended to be people trying to steal copper. Many times we had to hire security people to babysit our reels that we had leave at night in the middle of a job. IMHO, The metal buyers need to be more stringent when buying melted down copper from their customers