Am I correct in assuming that exchange-traded warrants are free to hold short overnight with IB? Can't find any info on the SLB Tool. Thanks
Yes. They are free to hold overnight like any stock. If they are hard to borrow there may be a fee to pay, You may also receive a buy in notice if the firm cannot no longer borrow the shares.
A short position is free to hold overnight if it is easy to borrow. If it is hard to borrow you have to pay a fee,