Well, great. Now I am wondering if my UNO R3 is legitimate, too. It came from Amazon but a different seller, Silverstone LLC. Looking closely at the web site photo versus a scanned image of the back of my board, things mostly look the same, but I see a string of characters on my board on the "upper right" (as seen to make the back text readable, IOW on the surface behind the reset button). The characters on my board, which are not on the arduino.cc photo, are respectively:
A circle with T.E. inside it,
A funny stylized S shape,
Three parallel lines like a triple equal sign or "defined as" sign,
011,
A reversed run-together UR,
94V-0.
Is this string of characters supposed to appear on the noncomponent side of a UNO R3, behind the reset button?
BTW I wrote a review about "Counterfeit, NOT an Arduino" on Amazon, we'll see if they post it.