If you share a new design,can someone steal your design?
Is there somethink protecting your design from someone using it?
Not a damn thing is protecting your design. If you want to protect your design the smartest thing to do is not to go public with it.
it would be very nice if there would be an option to protect your content by something like a creative commons licence. but this still isn´t available today(i asked the cc-people already when this will be possible but got no aswer...)
maybe grabcad should start with it...
the basic answer is no, but that shouldn´t be the last word.
Share only renders. Someone wil come up with a different idea, or design. Probably better than yours. Then it's your turn to steal...