Star Trek

I just saw that the entire franchise of Star Trek is now available to buy on iTunes with the exception of TNG. They recently completed DS9 and Voyager, and even have both original and remastered versions of TOS.

I'm wondering if it has something to do with copyrights or something, because all of the seasons are complete except for Season 4 of Enterprise, and when you look, every episode is there except for These Are The Voyages. Which was a TNG crossover.

But that doesn't make sense because Voyager is complete and it had TNG crossovers. And so did DS9 and it's all complete.

I have no idea. I think it would be awesome to see TNG added. Anyone know why it's the only one not there?