Hi,

in books like "501 Tesuji problems" or "Attacking and Defending Moyos" you can find problems that i would consider as middlegame josekis ( common attacks on a two-point extension for example ). A big disadvantage of these books is that these problems are not arranged on a special topic, so it is difficult to study certain positions. My idea is to collect these middlegame-josekis/tesujis arranged on topics in a sgf-file similar to Kogo's Joseki Dictionary.

I know that "Kogo's Joseki Dictionary" uses the Ishida and "38 basic josekis" as a reference.
But it is legal to use sequences of books and other sources for a free sgf-file which can distrubuted? ( I have not the intention to copy the text. ) I hope that there is no copyright on standard moves.

IANAL, but this kind of question has been been discussed here and elsewhere online for years. Here is my impression:

Copyright laws differ from country to country. In the US there is a court ruling that chess problems are not copyrightable. (However, commentary is copyrightable.) That would probably apply to go problems, as well. In Japan it seems that problems are copyrightable. Pros buy problems from other pros.

I doubt if joseki themselves are copyrightable anywhere. However, variations in a commentary may be copyrightable in Japan.

There is also compilation copyright, where a collection of non-copyrightable material may itself be copyrightable. Compilation copyright might apply to a joseki dictionary.

Complicated? Yeah.

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