We will not and cannot sign an NDA strictly for your Build Your Own product. While we will never publish designs created for you without your permission, the Build Your Own application is only low cost because of our ability to re-use individual component designs.
We utilize Altium Designer, specifically Altium's device sheets. Every component you see online already has a fully designed device sheet in Altium that we aggregate to complete your design.
So while the completed design will only ever be shared directly with you, the modular designs of individual components are re-used for multiple customers.
Here's an example of a device sheet for the Electric Imp enabled Murata imp004m module.
The device sheet can be expanded to reveal the contents of the design as shown below.
A complete schematic design becomes an aggregate of device sheets as shown below. Your complete schematic design will never be published or shared publicly.
Our engineers still have to create the layout and routing of your board. Your board design will also never published or shared publicly.