arbitrage opportunity

I understand the only condition remaining on the RMS bid for DIO is FIRB approval, which is unlikely to be denied.

Given that RMS cannot withdraw its bid, I can't understand why RMS shareholders aren't trading the arb - ie selling RMS and buying DIO - its a no lose situation and an opportunity to make extra money. Its effectively an opportunity to buy back your RMS shares at a lower price.

In the process the price of RMS will go down slightly and the price of DIO will rise until there is a slight discount in the DIO share price, not the whopping 20c at the moment.

One reason its not happening on a large scale is that RMS cannot be shorted - so its only RMS shareholders who can do it. Its one for the retail investors given the lack of major liquidity in both stocks.