I'm short some 267 SPY puts and trying to determine if I'll get assigned or not. SPY doesn't stop trading until 4:15 ET. However, TD, yahoo, google, etc. report the close at 4:00. It was close to 267 at 4:15 ET. Is there a place that lists the official closing price of SPY and other ETFs that trade until 4:15? I would define "official" as being the last trade that took place while the options market was still open.

