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How to Tell

A refurbished device that has gone through the Microsoft Authorized Refurbisher (MAR) program will have a Certificate of Authenticity (COA) or GML (Genuine Microsoft Label) on it. The COA will say it is for Refurbished Device and will also give a brand name for the Microsoft Authorized Refurbisher who refurbished it. See below for a COA example. GML is used when Product keys (activation code) is a part of Windows. See below GML example.


  • Special Colour
  • Special Wording
  • MAR Brand name


  • Holographic image displays Microsoft® in three depth levels
  • Color-Shift area, Blue to Purple by changing the viewing angle
  • Holographic Micro-Text
If you want to check whether a refurbisher is currently a member of the Microsoft Authorized Refurbisher program you can visit the 
MAR Directory