***I have no idea if this post is removed as it disappear after I post it, so I post it again, if it is remove, I hope I can get a notice from the ADmin.***
Patent is always a term used by design thief and copy cats to defense when they are being accused of stealing other's design! It is not for design or product design!
I knew many people said that pinhole camera already exist for many years. Yes, it is true but can you find a brand or any individual who that can make a wooden one with the short focal length of 25mm that can accept any 120 roll film with a compact size of 5 1/4" (L) x 1 3/4" (D) x 3 1/4"(H) including all knobs and comes with an exposure scale and viewfinder before 1999? I've been doing the research for 20 years but still have no luck. By that time we don't have any FB, we use 56K modem for internet, the pinhole society is Pinhole Visions...
Or can you find a commercial curve plane pinhole camera with multiple pinholes before RSS? (now we know who made such camera for personal use before, so bad I have no chance to see this camera before...)
To respect the camera makers, please have more research on their history, how they develop/design their cameras, how many researches works they have done, how their idea is come out, how they choose the material which is suitable for different climate of different countries, their craftmanship (using CNC router is definitely not hand-made) and their reputations, Why supporters willing to pay several US hundred dollars for their cameras, or even more money for a custom-made one, definitely it is not JUST A BOX. They have to settle many problems from production to after service, that is quite different from just make a single one for personal use. Shameless design thief can get the benefit of their hardworking by just have a little bit modification!
Just for example: even you use the same idea of curve plane camera with two or 3 pinholes or even 4 pinholes, I can't see why we cannot have just one shutter to open and close the different pinholes vertically, that's easy. (Please don't copy my new idea!

) This is the big different between new/unique design and a copy or a little bit modification!!!
I understand that the whole world need to improve, copy is a stage of grow up for some late comers who need to learn, but after learning should be showing their own works, not the copy works. Now is already 2020, Nikon or Canon no longer need to copy Leica M10 Monochrome! 20 years before we don't have affordable CAD CAM, Software, don't have CNC router, don't have 3D printer, don't tons of information and youtube. Entering a university to study product/industrial design is not as difficult as before! Still need to copy or steal other's design? Really a shame that they don't use the brain to design but use it to fool the public for money!!!
Actually making one's own pinhole camera is the best way to explore the pinhole world. The material you choose for the camera, the focal length you prefer, the film format you love, especially the pinhole you make.... all make your final images unique and different from the others. For those who choose to buy a commercial one, they pay for the hardworking, pay for the unique design, the craftmanship, the after service, and their contribution to the pinhole world...otherwise, it worth nothing!!!
Thank you for your reading, enjoy pinhole photography and please support original design.
Disclaimer: This response is purely for the discussion of patent, design rights, design process, copy method, design thief and pinhole cameras, no intention to specify or aim to anyone or any company/brand. If it is not appropriate, feel free to remove my post.