Posting an open source device for free to the world.

[magnetman12003]

With respect to patenting a device if you post it OPEN SOURCE free to the world can others patent your device?

[Floor]

Not in the US.  To be pattented in must be new.  If published first it is no longer novel (new).

            floor

[blueplanet]

I think they can.
Patents can be granted for an improvement on a known device or methodology.
Heat pipe is an obvious example. It was re-invented many times.
Drinking birds were already invented in China. It ended up being patented by Bell Lab some decades later.
In the US, a judge has an authority to take off the ownership of a patent from an inventor and re-assign it to another inventor.

All the prospective inventors need is to make up some claims which appear to be totally new.

[tinman]

With respect to patenting a device if you post it OPEN SOURCE free to the world can others patent your device?

Yes they can.
It's a first in,best dressed situation.

The only time you cannot patent a device,is if there is a device the same already patented.
I believe in order to patent a similar device,there must be a 30% change in design of the device,but it may achieve the same outcome.

[tomd]

The arduino board is open source. The design files are licensed under a Creative Commons Attribution Share-Alike license, which allows for both personal and commercial derivative works.  https://www.arduino.cc/en/Main/FAQ#toc3