They are different companies. They have lots of different offices around the world. They have about 5 or 6 broker-dealers in total.
FINRA retail b/d, CBSX, some overseas brokerage firms too as well as now owning the company that made old Blackwood Pro platform (formerly pacmid, now called fusion.) They also run quite a few hedge funds.
As far as I know the management is separate. The owners from the canadian firm may own part of the US firm but they are run as two completely different entities. the cbsx bd and software companies are headquarted in NY but have about 20-30 different locations around the US. I might be wrong about this but I believe they're the largest prop firm (in terms of volume) in the world.
Again, I am not recommending you use them. I do trade with them, however. The prop industry used to be much more decentralized and there were a lot of completely independent firms on the street but nowadays WTS is the largest prop out there.
DISCLAIMER: I am not recommending you trade with WTS. Despite trading with them, the above statements are purely fact. Do not in any way, shape, form, scope or measure consider this any type of recommendation to trade with them. I personally enjoy trading with them; however, due your due diligence before joining any prop.