You have to compare the potentials for your stock following a merger versus what might happen if you sell your stock before the merger. Review the total value of the stock you would have after the merger and compare it with what you have now. Determine the total charges involved. Check on the financials of the company that is involved in the merger. Sometimes the financials suggest that the business will grow and have a higher rate of profit, thus leading to a better stock price. Even better, you should review the trading history of the company you would acquire stock in. The new stock might be a strong performer, thus giving you a purpose to hold onto your investment and take advantage of the merger.