how i can view the license key for my Visual Studio 2012 professional

I have visual studio 2012 professional installed inside windows server 2008 R2. now i want to view its license key . i tried searching these locations but could not find any info about the license key for my Vs 2012 professional :-

C:\Program Files\Microsoft Visual Studio 11.0\Common7

C:\Program Files (x86)\Microsoft Visual Studio 11.0\professional\1033

C:\Program Files (x86)\Microsoft Visual Studio 11.0\professional\1033

C:\Program Files (x86)\Microsoft Visual Studio 9.0\Setup

so can anyone adivce on this pleae ?