Transfer CIA clearance between contractor companies

What is the process if say one were to transfer their CIA clearance from Contractor Company A to Contractor Company B and has anyone had experience sucessfully doing this?

I think Contractor B just has to do a little research to make sure they can see you in their database or however they verify clearances. At any rate it all has to be done from the contractor’s security office. But see if you can find out the dates that your investigation was completed and clearance granted… that’s always helpful information to have on hand