Author: Bret Gordon
Here are the logos of the various Judo organizations that operate here in the United States (that I know of at least). The top 3 organizations are generally considered the national governing bodies for the sport of Judo, and some of the other organizations have a working relationship with them, but ultimately they all operate independently and have their own standards and requirements.
Some people will tell you that if you don't belong to one of the "Big 3" then you are not a legitimate judoka and your rank is invalid. In nearly 28 years of martial arts training, if I have learned anything it's that there is never a single source of legitimate certification. For years, the Kukkiwon tried to spread that they were the only source for legitimate Taekwondo ranking but the comeback of the Kwans has proven that to be false. It is the same in Judo.
Rank exists merely to measure one's progress according to the standards of the person/organization issuing it. It is not a measure of skill, and it is not uncommon to hold different rankings in the same art from different organizations. One gentleman I know holds only a 3rd Dan with one of the "Big 3," but actively wears and claims his 5th Dan from one of the independent organizations when he teaches and promotes his school. Does that make him a fraud for saying he's a 5th Dan in Judo? I don't think so, but I'm also not the Judo police.
At the end of the day, what patch you wear or flag you display shouldn't be the deciding factor of legitimacy. If the person issuing the rank or running the organization is of high enough rank, license or appointment to do so, it is legitimate. With the rise of other martial arts, the Judo community should (in my opinion) be looking to bridge the gaps and bring everyone together, finding the common ground in our passion and training, instead of fighting amongst themselves for hanging the wrong banner. If the general public knew how martial artists treated each other, no one would ever enroll again...