Non Disclosure Agreements are common features of intellectual property law. The Patent and Trademark Office maintains all patent applications in confidence until a patent is awarded at which time the patent application becomes the patent. Before the patent has issued, the inventor should treat the invention as a trade secret unless it is being sold to the public.
Before a public disclosure takes place, anyone who needs to see the invention should sign an NDA. For example, a mold maker, a potential investor, or the like should sign an NDA before the inventor discloses the invention. The signer of the NDA acknowledges that the invention is a trade secret and agrees to maintain it as such.