Do artists (such as the Propellerheads or similar) need to gain permission to remix another artist’s song?
For example, Professional Widow by Tori Amos was not only remixed but appeared on the Boys for Pele album so obviously this was approved. But Fatboy Slim "remixed" I See You Baby by Groove Armada - so did he need permission to do that?
To release a remix that you have done on your own initiative, In most countries you will need to agree terms with the original artist's record company.
However, in many cases the remix artist is actually asked (and paid either a flat fee, or a percentage) by the original artist's record company to do the remix, allowing the song to gain the interest of sections of the market that the remix artist has specific expertise in.
I am pretty sure this has nothing to do with the recording company as they handle all licensing for their artists song repertoire through a PRO.
Usually you obtain what is known as a "use license" from a PRO (Performance rights organization) and you pay a fee to them which goes to the original artist for the rights to use their song.
Each case is different based on the originating countries licensing laws, but basically you enlist a company such as ASCAP, Harry Fox Agency, BMI and then work with them (and their team of lawyers) to finalize the clearance to use the tune.
Lots of good info on it here (For the U.S)
I fully agree with topo's answer, though on many occasions I've known a remix to be done initially without any permission, just to see if the track will gain any traction on the dance floor, as a white label.
Only if it does see some good feedback do the record company then go to the copyright owners for permission, based on the 'if it doesn't sell, no-one will care' assumption, which lawyers may argue over but is usually not worth the effort.
I've then known for the original 'borrowed' samples to be re-recorded to save having to pay the full royalty for the usage, instead only having to pay some smaller amount for a 'sound-alike'
In one specific case, after doing the re-record, the remix artist was then tasked to 'remove all copyrightable elements' of the re-record - by subtly changing chords, melody lines etc - until only the hint of the original track remained, yet enough to still give the feeling that it was the inspiration for the part.
Case in point - Inaya Day - Nasty Girl
https://www.youtube.com/watch?v=6R4hsN6snFc
The final release is a complete re-create, with changed structure - sufficient to keep the lawyers happy.
The original dance floor release contained samples of Michael Jackson's 'Don't Stop til You Get Enough' which was later cleared for use with the copyright owners, but not used in the hit single release. Source/disclaimer: personal experience, I know the creators of the track & how the negotiations were done towards the final release version.
