As a result of the market's calamitous machinations over the past year, for several months both the New York Stock Exchange and the NASDAQ suspended listing requirements on their indexes, leaving companies the freedom to ride the daily ups and downs without fear of being kicked off the boards. Citigroup ( C), for instance, flirted with the dollar line back in March. But at the beginning of August, with more and more positive economic signs bubbling about, the exchanges began enforcing the rules again. There are, of course, a slew of requirements that a company has to meet in order to stay listed. Bid price thresholds are one. On the NYSE, that means companies closing lower than $1 over a 30-day trading average face possible expulsion. On the Nasdaq, companies closing lower than a $1 on 30 consecutive days will have to account. Still, the announcement that a company received a deficiency letter from one of the indices isn't a death blow in itself. Rather, a company will enter into a six-month purgatory of sorts, where the stock continues to trade. If a company wants to stay listed, it'll use those six months to move shares higher. In the NYSE's case, officials explain that once a letter is sent, the deficient company will present some sort of plan of action to exchange officials. That could include a reverse stock split, a merger or any assortment of options. Generally, in order to be deemed compliant, shares must close above a $1 over a 30-day trading average. At the end of the aforementioned 30 days, the price must also meet the $1 threshold on the closing month's end (or on the final day of the six months following a 30-day run-up) during the proving period. In general on the Nasdaq, shares must close above $1 for 10 consecutive days for the company to get back in to the exchange's good graces. If not, generally both exchanges begin the process of formally delisting shares, which could involve appeals and final committee determinations. In the Nasdaq's case, however, there's an added wrinkle: After the 180-day period, shares for the company can be transferred to a sort-of minor league tier known as the Nasdaq Capital Markets. There, shares will trade while the company in question attempts to use another 180 days to raise share prices. Hypothetically, then, a Nasdaq-listed concern may have as much as a year to raise its share price from the moment it's considered deficient.