A Question About Sunken Ships

The Italian liner “Andrea Doria” sank in 1956. I assume that the insurance company/s which insured the ship have paid the owners long ago-so who owns the wreck today?
Since the 1980’s deep sea divers have been diving to the wreck-removing china, statues, and other artifacts.
Suppose I were to vist the wreck, and found a ton of gold bars-would the insurance company have a claim aginst me?
Or are all shipwrecks considered “abandoned property”, after a certain number of years? Are you free to take whatever you want from them?

Depending on the waters that the wrecks are in, many governments claim ownership to treasure.

Check this out: Shipwreck - Wikipedia