This is well explained here: https://support.arduino.cc/hc/en-us/articles/360020652100-How-to-spot-a-counterfeit-Arduino https://support.arduino.cc/hc/en-us/art

This is well explained here: https://support.arduino.cc/hc/en-us/articles/360020652100-How-to-spot-a-counterfeit-Arduino https://support.arduino.cc/hc/en-us/articles/360020652100-Ho... A counterfeit is a product that tries to deceive customers making them believe that it's manufactured by someone else (regardless of the open source nature of its design). Open source hardware design only makes for a part of a commercial product and does not cover manufacturing, supply chain, quality of components, warranty, customer support etc. etc. for which it's important to distinguish who is the actual entity responsible for that product.