Can a delisted stock be relisted?
A delisted stock can theoretically be relisted on a major exchange, but it's rare. The delisted company would have to avoid bankruptcy, solve the issue that forced the delisting, and again become compliant with the exchange's standards.
What's more common than a relisting is that a delisted company goes bankrupt and the delisted stock becomes worthless. The company may be acquired by a private owner out of bankruptcy or be forced to liquidate. The company may also restructure and eventually go public through an initial public offering (IPO), issuing new shares to new shareholders. While the company is the same, the original shareholders generally have their investment wiped out in the bankruptcy.
How to sell a delisted stock
If you are aware of the possibility that a company may be delisted, choosing to sell your stock is probably a wise move. Involuntary delisting and the events leading up to it lower a company's value, and, if bankruptcy occurs, there's a good chance of losing your entire investment. When a stock is delisted as part of a merger or due to the company being taken private, you have limited time to sell your shares before they are converted into cash or exchanged for the acquiring company's stock at a predetermined conversion rate.
While you can still sell your shares when a company trades over the counter, the bid/ask spreads may be relatively wide, meaning that buyers willing to pay your desired price are scarce. Although some brokerages restrict such OTC transactions, you generally can sell a delisted stock just as you would a stock that trades on an exchange. A delisted stock can continue to trade over the counter for years, even if the company files for bankruptcy.
In case you think that buying delisted stocks represents a bargain, this pitfall is best avoided. These companies are often in the process of bankruptcy or are severely financially challenged and tend to trade like penny stocks.