See the following resources for current ticker symbols:

• Go to Ticker Symbol Lookup
• Bloomberg; available at the Margolis Market Information Lab (MIL) in the Business Instructional Facility (BIF).
• ValueLine

Delisted or changed ticker symbols:

• Come to the Margolis Market Information Lab (MIL) in the Business Instructional Facility (BIF) and use Bloomberg.
• Check whether the New York Stock Exchange is planning to delist a company by visiting NYSE-Regulation: Delistings
• Listing Standards:
  • NYSE-Regulations--Listing Standards
  • NASDAQ-Listing Standards and Fees