Condo Lease Renewel

I currently lease a condo from a private owner. My building has apartments that rent from the building management. I received a "lease renewel" pack it to fill out from the new building management along with a $50 fee. I have no issues with filling out the 20 page package but I do have issues with giving them my social security number and the fee. Again, I do not rent from the building management company and have rented from my landlord for 16years. He did a back ground check and credit check on me 16years ago. He agrees I should not have to just give up my social but the new management company is threatening to fine him every month I refuse to give my social. I have nothing to hide, but I do not appreciate being bullied from people I don't even pay rent to. Can they do this legally?