I don't think Picamilon not being sold has anything to do with rights; it's not patented as far as I know.Apparently it's as efficacious as any benzo and with none of the downsides like addiction and loss of efficacy. My neurologist - who is Russian - agrees it's an amazing drug and wishes we could get it here...but we can't. Sorta kinda at any rate. You can find it online but seems to sketchy to risk it. I have no idea how one goes about acquiring the rights to sell it here but I'd imagine a small fortune is waiting to be made for whoever can.
Picamilon was available in the US via multiple sources until late 2015, when FDA's crackdown on it followed:
https://www.fda.gov/food/dietarysupplements/productsingredients/ucm472881.htm
I tried Picamilon quite extensively and it had very little efficacy compared to benzos, which I've also used infrequently.
They cannot be mentioned in the same sentence, in my humble opinion. That said, this was my personal experience.