As often happens in 3D printing, where the term often seems more like a marketing term than something informative, this is not open source by commonly accepted definitions. (The title here inappropriately says 'open source', as the page title does not.)<p>These models themselves are CC-BY-NC-SA, which is not open source because of the non-commercial restriction. Non-commercial is also vague, and my understanding is that with 3D printing some people using the license have even argued that NC prevents users from ordering prints from a print service rather than printing on their own printer, or prevents someone from being reimbursed for filament costs.<p>To make matters worse, however, these rely on Multiboard for mounting, which is <i>decidedly</i> not open source. Multiboard uses its own, long, proprietary license [1]. Amongst other things, it appears:<p>- you cannot print it for anything other than <i>your own</i> personal use (no printing for others, even for free), and agree to never give or even loan any <i>printed</i> items to anyone; you even agree that you won't 'encourage' third-parties to give physical prints to anyone else,<p>- you cannot publish modified versions unless they are "substantial", and you agree to license any of your modifications to them (their 'non-binding summary' says that license doesn't include selling them, but the binding license itself definitely seems to include it),<p>- you agree that you won't 'do anything at all contrary to the interests of' the company,<p>- the company can at any time, for any reason, terminate your (or everyone's) ability to make modified designs, and can also terminate your license entirely for any breach of the license (which, remember, would include doing anything at all contrary to their interests). It's not entirely clear what that termination would mean for physical prints: at best, it would make it impossible for you to expand a system you already have, though I would not be surprised if the company tried to claim it would prohibit you from using the items you've already printed.<p>[1]: <a href="https://docs.google.com/document/d/1C0-Iyxydqk_d2I3o_5ualJ9Ywt9gwVdl9eukvC8JeKA/edit?tab=t.0" rel="nofollow">https://docs.google.com/document/d/1C0-Iyxydqk_d2I3o_5ualJ9Y...</a>