Four out of five are from CA. I hope that's a coincidence.

Ugh. Just because they live in CA now doesn't mean they are from CA originally.

I don't have time to go back through the files, but if do a Google search on the GITS site -- "Nicholl Fellowship" -- you'll see the winners back to 2008. And if memory serves, each year a majority of the winners have been from California [not all LA]. That said, I know some Nicholl winners personally who lived outside LA when they won including one who resides in North Carolina. My guess is the California 'connection' isn't so much about needing to live in LA or whatever, but rather that CA is such a big-ass state with a big-ass population base. And proportionately probably has a greater sense of awareness of screenwriting amongst the general population, especially SoCal, and specifically about the importance of the Nicholl.