Soviet intelligence had obtained it from a high-placed mole in Tokyo but did not want to compromise their own security by publishing it openly, so they had leaked it through contacts that they had in the United States.
Intelijen Soviet mendapatkannya dari sebuah gedung tingkat tinggi di Tokyo namun tidak ingin keamanan mereka sendiri terkena getahnya karena menerbitkannya secara terbuka, sehingga mereka membocorkannya melalui kontak mereka dengan Amerika Serikat.