And the Arduino designers do not object to people copying the electronic design (even less so if there are design changes like substituting in a different seria

And the Arduino designers do not object to people copying the electronic design (even less so if there are design changes like substituting in a different serial chip). What they ARE objecting to is people copying the branding and graphics (down to the "made in Italy"): https://blog.arduino.cc/2013/07/10/send-in-the-clones/ https://blog.arduino.cc/2013/07/10/send-in-the-clones/ Still, different serial chips mean different device drivers, so one product shouldn't be sold under the other's name.