The juicest bits from the above website:
Stefano Surace sensei holds the highest official Ju Jitsu grade in the world, recognized in Japan: 10th dan Menkyo-Kaiden, member of Nippon Seibukan.
The Dai Nippon Butokukai was the Imperial Martial Virtue Association until the end of WW2. The best masters of the 11 most important Ju Jitsu schools were brought together there and were in charge of elaborating a synthesis of the most efficient techniques of each school.
Particularly rational and structured, this "supreme method'' was only taught to a selected élite which refused to ensure its diffusion after 1945, for the sake of coherence with its Japanese traditional ethics.
By an exceptional combination of circumstances detailed in Surace's book (available in French) "La plume et la main vide'', the last holder of this method is now Stefano Surace.