Everyone is entitled to express their opinion. What is not acceptable is a rude and inflammatory tone when expressing such opinions - especially when the GUEST in question has acknowledged their own rudeness, and clearly not even read the thread!!

I must admit I was a tad annoyed when I read the thread subject, but when I clicked and read it properly I discovered that it was essentially a new enquiry on a very 'sensitive' matter, which most people seemed to have respected and responded to in an helpful manner...

In the folk world there is a tendency for people to try to make money out of 'Public Domain' material by copyrighting their 'arrangement'. Whether their argument would subsequently stand up in a court of law depends, I think, largely on whether that 'arrangement' has added something to the song/tune other than simply playing the tune and chords...!

The difficulty, say, with a Copper Family or Watersons vocal harmony (for example) constituting an 'arrangement' is that such singing has been handed down over many decades and no one can precisely pinpoint when it became an arrangement for copyright purposes other than at the time when a recording was made. However, they have a distinctive sound which sets them apart, and this could well provide the basis for argument.

Certainly, Carthy's arrangement of 'Scarborough Fair' is a one-off, and Paul Simon's guitar arrangement, whilst not being the same, clearly owes a lot to Carthy's. Simon also changed the tune a little to make it more 'commercial', but it is clear where his ideas came from - after all, at the time he was touring British folk clubs (Leigh Folk Club paid 12 shillings and sixpence for him to appear!), and 'Homeward Bound' was written whilst sitting on Widnes railway station!

It's certainly a bit of a minefield to say the least, and I echo the opinions of all above who suggest that research is essential. Sadly, it would still be possible to fall foul inadvertently - most of us know the story of the late George Harrison's 'My Sweet Lord' which cost him a packet when the Chiffons managed to 'prove' he had plagiarised their chord structure from 'He's So Fine'... sorry, but I still believe it was nothing more than a clever lawyer... though legally I can't say that!!

Good luck, mate!