SDLT - data-sharing between HMRC, Land Registry and DWP

Hi I have limited understanding of SDLT. I believe when you buy a house, you have to pay SDLT if it's over the threshold and the Buyer completes the forms to do this HMRC ask for National Insurance Number. Do HMRC then do further checks or supply data to land Registry or DWP and what data do they share ?

Hi,
Hi,
Please call HMRC  for help with Stamp Duty Land Tax queries:
Stamp Duty Land Tax
Thankyou