Interesting explanations at the linked files. The old rule for seagoing vessels was that the child could potentially be considered a citizen of one or more of the following countries:
- Mother's country of citizenship
- Father's country of citizenship
- Ship's country of registration
- Country of ship's last port
- Country of ship's next port
- Country of ship's scheduled destination (if not the same as the "next port") case.
I've seen (but can't find right now) references to children born in transit who needed to sort out which of the 6 possibilities listed above would be their final nationality. Note that with a very few exceptions, the US does not recognize dual citizenship. Rather, the child must decide at age of majority which citizenship they will assume (and give up the others).
As usual, I am not a lawyer; laws may vary in your country; objects in mirror may be larger than they appear; your milage may vary...
Xenophon