"Some may express concern that the Free Universal Construction Kit infringes such corporate prerogatives as copyright, [etc.]. [...] the public is legally allow

"Some may express concern that the Free Universal Construction Kit infringes such corporate prerogatives as copyright, [etc.]. [...] the public is legally allowed to make 3D prints that mate with proprietary parts, especially in cases (the “Must Fit Exception”) where a piece’s shape “is determined by the need to connect to or fit into or around another product”" Further down he notes that this only holds for private and non-commercial use.