I feel a bit disappoint that this has got so many votes on HN, when a simple Google image search shows that the icon in question is a simply a freely licensed image produced by FreeIconsWeb that turns up when you search for "copy icon".

I'm guessing the author of this article knew that (presumably that's where he got it from) but chose to omit that rather critical point from his post to make it seem more favourable to himself.

Link to original image: http://www.freeiconsweb.com/Icons-show/Freeicons/Copy.png