Quoting Frogboy, reply 1
Unless I'm missing something, Folderview also seems more flexible.
Fences has been in internal alpha (it took a LONG time to get this to work on Windows) for years. There are screenshots of it on our site from a couple years ago.
It still doesn't answer the (implied) question "When was Fences actually released ?" If, as it appears to be the case, KDE4's Folderview was released before Fences, calling it a clone(or inspired by) of Fences is a stretch.
It doesn't matter when it was released. As soon as the idea is made public, anything coming after can be considered a "clone". It doesn't necessarily mean that the developer has even seen the original software.
Bumptop is a good example, there are numerous clones out there, and bumptop isn't released. All similar software (such as realdesktop) are still clones.