Do old landlines on my property belong to me or Spark? As in, could I take the copper feeding my former telephone connection up to the pole and sell it for scrap?
I don't think there is ever a bad time to talk about how absurd war is, how old men make decisions and young people die. - George Clooney
Chorus own the copper and it's part of their network up to the demarcation point which will either be the ETP (if fitted) or the first jack point in the house.
Taking it would be theft as it's not your property, and at best a scrap metal merchant would want you to pay them for it as the amount of copper in a lead-in is of no value to them.