不过从风险/回报的角度，还是该持有吧。

If merger goes through, OSIP will dip a little bit. If merger does not go through, OSIP will rebounce strongly because so many risk-arbitrage people who have shorted this stock have to unwind (i.e. cover) their short positions. If chance of merger failure is about 50%, risk/reward is favorable for your speculation. Again, your money, your decision. It is not my favorable trade.