I think the misconception is that IP is solely owned by one person, or company, group, etc. IP rights have to do with the commercial profit of using IP. The originator has commercial protection, if they enforce it, say by copyright, etc.
Take the Ramform hull design and parameters, for instance. It's Patented, and has a registered trademark, even for the name 'Ramform'. I can apply everything in that patent, and legally build a Ramform vessel, without permission, or the approval of Roar Ramde, or PGS, and plan to. What I CANNOT legally do, is produce it as a commercial product.
Whether or not it will have any intrinsic resale value is immaterial. I am not producing a commercial product. How I APPLY the USE of the hull is only important if it becomes a commercial use, related to the intended commercial uses, listed in the patents.
I have no intention whatsoever of making and selling hulls, using it as a survey vessel, or FPSO. My own purpose is as a residence, and potentially farming at sea.
Anyone can copy and build a barn, house, etc. However, if there is commercial production of that design, then there is the potential infringement on IP rights.
This is one of the arguments I had with Wil Elmer, some time ago. I've done my digging. I know MY application is NOT what everyone is dancing around, in this topic, but it's a good example of IP rights, and what they are/are-not.