SPY trading hours

Does someone know which are SPY's trading hours?

 

Must be real hard one, 45 looks, and not one answer.

 

Define SPY in "SPY's trading hours".

 

regular market trading hours
9:30 to 4
with some premarket/aftermarket trading in there
i believe 8-930 and 4-630

 

Actually, it is a hard question. And finding the answer takes some time.

4AM - 8PM is what I see so far for one or another of the US based exchanges.

 

I had the doubt if SPY trades in the same time-frame as the S&P futures.

Thanks!

 

ARCA opens at 4AM now.

 

http://www.amex.com/SPY/aboutSPY.html