Ged Fox.. In the case of the UK and song ownership, Modern copyright is for 70 years after the death of the author/composer. If a work has more than one author/composer - then it is for 70 years after the last person involved died. If you have made a significant change to a trad. work - added lyrics or tune, then you can claim the arrangement of the work Trad Arr by. Or if really changed, claim the whole work as original. Modern copyright exists from when the work first appears in a fixed dated form, which is why it is usually the standard to put (C) - then e.g. 1962.