Indiabulls Securities, a demerged entity from Indiabulls Financial Services, today listed at Rs.300 on the Bombay Stock Exchange (BSE) but soon tumbled to Rs 110 within few minutes of the stock opening.Indiabulls Financial Services backed by the steel tycoon Lakshmi Mittal, gave one share for every share owned to its existing shareholders in the new securities company after the split.The BSE had suggested its members a reference price of Rs. 596.65 and Rs.380 for the spin-off entity.