vor-I was not implying that a not-for-profit would have more rights. I have been told that you are more likely to be given a permit to go after sunken ships and other treasures. I am going to look into all of this in the near future.
They mean not for profits like the Florida Aquarium...I don't think any new permits have been issued to any "regular people" (not for profit or otherwise) in a looooong time.
I bought a few pirate books to see if anything showed up about the area you are looking into. One was pretty much all legend...and tied almost every pirate in the world to the fictional Jose Gaspar, as well as got a lot of the "facts" from Wikipedia, and "online forums" (probably this one since it kinda brushed on the Confederate gold story).
The other one seemed way more based in reality and more about the facts, and indicated what was most likely legend. Although anything about the Manatee river seemed to be speculation, it did mention a ship being run aground up the river, and some of the cargo being hastily burried in the banks of the river. This is a story that is tossed around in several books, but hardly ever attributed to the same pirate.
Some versions of the story (not necessarily from these pirate books) say that the treasure was burried in the pirate camp, then turn around and say that it was a ship that was chased up the river, the crew burried the treasure, then the ship was sunk or burned, and kinda contradict the pirate camp version. It is possible that they were two incedents that occured a hundred years appart, and that both, or neither, happened.
With all the stories of pirate activity in that area, I have to believe that they are based on some kind of fact, and that something happened there in the past. I hope it was a pirate camp, and I hope that some cool stuff is found there at some point.