Very recently a South Korean salvage team located the wreck of a Russian Imperial Navy cruiser (Dmitrii Donskoi) which was sunk in 1905 during the Russo-Japanese war. They believe the ship sank with 200 tons of gold bullion and coins worth $130 billion today. The salvagers have promised 50% of whatever is recovered to the Russians.
I am not a lawyer and salvage laws have always been a bit of a mystery to me.
My understanding is that a sunk ship belongs to the original owner unless they can be proved to have abandoned it. Abandoning it has to be explicit. Just leaving it there for 100 years without trying to look for it is not enough to be considered abandoned.
Perhaps more restrictive is (I think) that soveriegn ships (e.g. warships) are forever and ever the property of the country they belong to and cannot be legally salvaged without their permission.
But in this case the government who owned the ship was the former tsarist government of Russia. Since then there have been two regime changes. One to the Soviet Union 1917 and another government change in 1991 when the Soviet system collapsed and formed the current government.
So, legally, can the Russians claim ownership of this wreck or can the salvagers claim the government the ship belonged to no longer exists and take it all for themselves?
(Note that the wreck is in South Korean territorial waters and they would likely tell the Russians they can’t salvage the wreck if they didn’t allow this salvage so this may well be their best deal…just asking out of curiosity.)