any insurance you may have on the boat?
It seems that if I told my insurance company that I 'sank my boat on purpose', they'd be a bit reluctant to pay on my policy. Admittedly, abandoning in mid-ocean makes recovery somewhat unlikely, but nevertheless, you might find yourself in an area where there was some dispute about recoverability. What's worse, is that in those questionable areas, the risk of higher traffice and collision with the derelict begins to increase as well.

Anyway, not having read the 'fine print' on this issue I'm throwing this out to those who are more knowledgeable.