I worked with a Palestinian for about a year and a half and he told me the story about how his wife was essentially "stateless". She didn't gain citizenship until she married him here in the US. Its been a while since he told me this story, but her family either lives in Jerusalem or used to live in Jerusalem and she somehow lost her citizenship because she had left for an extended period of time (going to school) and was denied entry back in. Apparently there is an effort by the Israelis to get as many of those people out of Jerusalem once they leave by putting time limits on how long they can leave the country. Of course, that doesn't apply to Jews that live in Jerusalem or Israel, that rule is only for them.
I'll have to ask him again to get the specifics, but that is what I remember him telling me. I worked with the guy for a year and a half and he didn't give the impression of being a fabricator or BS artist.