Is it possible to copyright an act? How is it done? Do you think it is important? If a performer seems to be appropriating work, is it best to confront or ignore? Defend idea.. or take as compliment??
I've answered this question before, so this time I'll give the short version.
My tone is going to be a bit brusque, not towards you, but towards people who feel entitled to use whatever they see to choreograph, teach, or perform others' material.
1) In the US, we copyright numbers like so:
If you don't have it in you to research the equivalent in your own locale, that's too bad.
Added note, the only legal advice with any value whatsoever comes from legal professionals. Backstage discussions don't count unless the people involved in them are legal professionals.
2) Most performers would rather be attributed and hired and paid than have their work "complimented" by "appropriation."
3) If you're thinking about doing a tribute to someone, the best person to ask is--BIG SHOCK--the person themselves!
4) Acts you think may be classic reproductions may not be. Acts you think may be original may not be. People you think are dead may not be, and even if they are their families or others may hold rights to their material.