Can I reproduce an existing font with Prototypo? - byte-foundry/prototypo GitHub Wiki

Traditional type design applications allow modifying existing font files or reproducing existing designs. And we are working hard on improving the creative possibilities of Prototypo to make creating any kind of typeface design possible.

In traditional type design applications or in Prototypo, the issue isn't whether you can technically reproduce an existing font, but what happens when you do. The answer to this question depends on the possible intellectual property protection of typefaces, which varies across countries. There is a well documented and sourced article on this subject on Wikipedia, as well as other interesting resources on the web.

In any case, Prototypo and other type design applications are just tools. You are responsible of what you create with it, and you should ensure you are not infringing on someone else's copyright. As a general rule of thumb, we advise against trying to reproduce an existing font with Prototypo, other than for personal experimentation. After all, Prototypo is here to help you prototype your ideas and create your own fonts. If you like an existing typeface, just use it and support the font creation by buying a licence : ) There are even excellent fonts available for free under permissive licenses.