<p>Hmm. This is interesting. I checked both “Native American” and “Caucasian” on the commonapp, but I haven’t received any kind of ethnicity verification form from Yale. (Then again, I haven’t received any acknowledgement of my application at all yet, so maybe it will come later.)</p>
<p>I’m not so sure that you actually need to be registered, though. I called Harvard (I know this is the Yale forum, but I imagine that much of what applies to Harvard in the application process applies to Yale also), and I was up-front with the admissions officer that I was primarily caucasian and did not legally belong to any tribe, and he still (very enthusiastically) encouraged me to put it on the application and send a separate note explaining it. Therefore, my guess is that you just need to prove your lineage in some way, not necessarily be registered yourself.</p>