How to know if a stock is marginable in IB? I tried to short IMCL on margin before market close today, the order was rejected to satisfy maintenance level although I used less than 1 time margin even the the order went through. I called IB, and was told that IMCL should be marginable since it is a 14 dollar stock, but they didn't find out why my order got rejected. I suspect that IB made IMCL as non-marginable during market time. It is very upset to miss a big move for such reason.