Well, the actual font files themselves are copyrighted, and can be distributed under whatever license he wants. It's just the shapes that are not. So you can't

Well, the actual font files themselves are copyrighted, and can be distributed under whatever license he wants. It's just the shapes that are not. So you can't take the font files, add or tweak a letter, and redistribute them. But you can go through, manually trace each letter, add or tweak some, and distribute that. I suspect that most people who would want to create a derivative work would want to reuse the existing files. Manually re-creating a font is quite a bit of work. Finding just the right control points to get the curves perfect is tough. And no, you can't just dump the control points out of the original file; that would be creating a derivative work. Edit to add: And actually, I believe that the copyright notice on that page is for that sample, displaying how the font is constructed. This is something that is copyrightable. The actual font file doesn't seem to have been released.