Yes... you see, there are thousands of martial arts, though some are blatantly diffrent others are seperate from one another only by lineage. The martial arts world is filled with arts that claim to be somthing or other while another art claims the same.
For example, among those that practice wing chun, you find thousands of people debating the orgin of the art and which variation can be considered the purest form. The Yip Man lineage or Ving Tsun or any of the other offshots

I find that the koreans are the worst about it, a good deal of the time they blatantly ignore their past connection to the japanese despite japans obvious influence. Sure taekyon was an art that predates the japanese inhabitation of korea, but most other arts where inspired by those brought over from japan. Judo became Yudo, Kendo becomes Gumdo, Aikido becomes Hapkido and various okinawan fist styles (but mostly shotokan) combined with native boxing methods to become Taekwondo. A good deal of the time koreans insist that their arts predate japan by thousands of years, and promote various myths for this cause.
Also...the gracies are the fathers of brazilian jujutsu, and dominated vale tudo and the UFC in the early years of MMA.