[Cboldt]

What you describe in relation to some of the islands is similar to piracy. Jurisdiction comes from subject matter or wrongs against e.g., citizens of the United States of America.

The fact that some isolated islands do not have the diplomatic protection of another country makes it easier to get them. Just go grab them, territorial jurisdiction or not, and no country has claim (let alone superior claim) on the grab.

I suspect most of the islands are claimed by some country.

[generally]

Thanks! Very helpful.

More rich island owners: DiCaprio, Johnny Depp.

[generally]

More rich island owners:

Shakira
Celine Dion

[generally]

more rich island owners:

Nicolas Cage
Mel Gibson