As ScenicViewer has pointed out, the currently structured Watchtower sect of Jehovah's Witnesses is itself a splinter group from a more antiquarian religion set up by CT Russell. After their founder's death, his followers assiduously attempted to carry on his teachings in an organized, thematic way conditioned on his teachings, including the jargon he invented.
But this was irksome to the then "President" of the "Watchtower Society" who inherited all the physical panoply that CTR had left behind, including all the cash, the landed properties, and the Watchtower subscription list. So, whereas he controlled the purse strings and all the aura of CTR, the original BS groups had to start off from scratch.
They were expected to die out and fold up, especially in view of the fact that they themselves were careening off into several sub groups. The fact that they have survived today, and are more tranquil than the current Watchtower stable, with its ever increasing rate of defectors, is a testament to the continuing influence that CTR has on his readers.
It is truly ironic that the man who set up the Watchtower publishing empire, and who invented this religion, would be disfellowshipped from the very movement he himself set up! He would however be at place, and peace, in any one of the BS groups that exist today.
When JF Rutherford, a man more at home with larceny and debauchery than religious authority, invented the "Jehovah's Witnesses" moniker, he effectively set up a completely new religion, crafted in his own image, and bearing no resemblance to the original set up, either religiously or emotionally.
Thus the current Watchtower religion only dates from 1931 and has been in existence for only 70 years. It is thus not old enough to have generated its own organized dissenters, but hang on till 2014, when something like "The Reorganized Worshipers of the True Jehovah" are expected to be formed!
There are, however several "Sacred Name Groups" out there, such as the "Assemblies of Yahweh" which might have been set up by former Watchtower followers since 1931.
The Watchtower's own antiquarian pretensions are at least inflated or even preposterous. For better or worse, the current religion that we know as "Jehovah's Witnesses" is the legacy of a man, JFR, who according to author Edmund Gruss, "maintained a process of governing that defied all Scriptural logic, and instituted a leadership that was a rejection of everything that Jesus taught". - [The Four Presidents of the Watchtower, E Gruss page 52]