I have to wonder how many code writers came up with the same or similar applications without knowing what others were doing at the time... or how many code writers saw an application and felt they could improve upon it using code of their own.
I also have to wonder how different one 'copy/move' program can be from another. They all do the same thing, copy and move files, and when you consider just how many software developers there are in the wild, there has to be some similarities or duplications that can be put down to coincidence rather than intentional copying of IP.
I mean, what if I come up with the idea for a flashlight that has a digital/FM radio, a TV tuner, connects to the internet and orders its own batteries? Oh, look out, somebody in Lithuania thought of that as well.... and somebody in the Congo improved upon it and added a laser cutter, GPS and a fold-out portable toilet for caught-short campers.
Then Apple comes along, says it thought of it all first and sues everyone. 
I suppose what I'm trying to say in a 'round-about' way is that we may know of this or that program that does this and that, and we may see others that do this and that as well, but at the end of the day we are merely outsiders looking in, and we can't know all the details and business decisions that led to 'same' or similar programs being developed.
