GQ published an article and excellent chart about this. From each distillery, you can see different branches, depending on the type of mash used:
The chart points to some interesting things. For instance:
... one would hardly imagine that the Blanton’s Distilling Company, W. L. Weller and Sons, and the Old Rip Van Winkle Distillery are all fanciful names for the same distillery, Buffalo Trace, that distills 60,000 gallons of mash into bulk spirit in a continuous still. While the four mash bills contribute to the flavor, the more significant differentiation among brands is done in the warehouse, where the type of construction, placement within the warehouse, and duration of aging have a stronger impact on the finished spirit.Full GQ article here.