Chubb did a fully collateralized bond. Meaning they got something of actual value, not just trump’s word. In this case a Schawb brokerage account full of stocks and bonds for (I believe) more than the value of the bond. Plus Chubb probably added a fee on top of the value of the bond to service the transaction. When trump loses the E Jean Carroll appeal, Chubb will hand over cash and sell off the assets in the Schawb account and pocket their service fee.