Listing and Delisting Requirements
Before a company can begin trading on an exchange, it must meet certain initial requirements or "listing standards." The various exchanges set their own standards for listing and continuing to trade a stock. The SEC does not set listing standards.
To be listed initially, a company must meet minimum financial and non-financial standards. Among other things, the standards cover total market value, stock price, and the number of publicly traded shares and shareholders a firm has. After a company's stock starts trading on an exchange, it usually is subject to other, less stringent requirements; if it fails to meet those, the stock can be delisted. As with listing requirements, the standards for delisting shares are not uniform; each exchange has its own requirements. You can find the initial and continued listing requirements on the websites of the New York Stock Exchange and the Nasdaq Stock Market. Neither the OTC Markets Group(f/k/a Pink Sheets) nor the OTC Bulletin Board has listing standards, although the SEC requires companies to be current in their filings before their stock can be quoted on the OTCBB.
You can find out whether the New York Stock Exchange is seeking to delist a company by visiting the Reviews/Suspensions section of the NYSE's website. The Nasdaq Stock Market has a similar list available online.