None of the schools specify validity of the GMAT scores. By definition, GMAC holds the validity of these tests for 5 years. The idea being that after that point there is enough reasons to believe your aptitude will be altered. However, some Indian schools require the GMAT to be taken in the last 2-3 years. If so, they will explicitly mention it on the website.
So in short don't worry about getting dinged because you got a GMAT score from 2010 as opposed to someone who took it in 2013. The nature of the test is such that it will always be tough to reach a particular score - the only thing that can change is the corresponding percentile. So a 750 in 2005 is as hard to score as a 750 today. In 2005 that was a 99th percentile - now it is a 98th percentile.
I would worry about the GMAT and make sure I take it when I am best prepared, and have the most time to focus on.
15 GMAT & MBA success stories | GMAT 750+ scores & Admits to Harvard
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