@Tomas
So what should you then do when this said group does not exist anymore??
I'd say you'd still be allowed to redistribute the original release as long as you don't ask money for it.
Nowadays party rules often have a clause that any release made at the compos must be redistributable by the organizers / others. Naturally there weren't such agreements during the early days, though.
Taking charge for the shipping and media costs does not equal selling, since the person who is doing it earn zero profit for the job of transferring the demos to video.
IMO without permission it's either totally free of charge or no distribution. Reversed: If you want to ask money, you need to have permission.
Also this would mean that it would be just as illegal to host most of these older demos on the internet for free, as it does not state in the copyright that these files can be hosted on the internet medium.
I don't see what is wrong with hosting the demos on the internet free of charge.
The simple fact is that most demos are released in public domain for free
Free yes, but I can't remember seeing any Public Domain demos.
What about all the amiga magazines with demos cds back in the day?
They had permission, clearly, except...
They also released a bunch of PD stuff without asking for permission and alot of people actually bought the demo magazines for the demo cd/floppy disk.
PD stuff can be released without permission. But unless if someothing clearly states it's Public Domain, you can't treat it as such.