From a quick scan of http://jigoshop.com/licence/ http://jigoshop.com/licence/ it looks like it's licenced as GPLv3. Unless I'm misunderstanding something funda

From a quick scan of http://jigoshop.com/licence/ http://jigoshop.com/licence/ it looks like it's licenced as GPLv3. Unless I'm misunderstanding something fundamental about how the GPL works, any fork is going to have to be published under the same licence (or can they exert proprietary control over the specific changes they make after forking?) Assuming the former, and that the new fork must also be GPLv3, I can't see there being a huge problem, the original devs can always merge in features from the fork into their version (although it sounds like they've been hired to work on the fork anyway) What does this achieve other than a rebranding exercise?