I was sure that it was after 5 years, but I've heard people say after 3 years. Also, does the first year count? In other words, I took the GMAT in October 2009, since there would be 3 registration periods in that period, would October 2009 count and would this year be the 3rd year? Or does it count as 2 years? Thanks.
It should be good for 5 full years after taking the test. Since you took it in Oct 2009, it's most likely good until Oct 2014. I don't know what you mean by registration periods. GMAT tests are given every day pretty much year round. With that said, because application first rounds begin in October, you may want to double check with adcom if you plan on applying in the fall of 2014.
FindIt - http://www.getfindit.com
My blog - http://www.shoescount.com