| Abbreviation | Definition |
|---|---|
| XKP | Lehman 2002-1 |
| XKS | Lehman Brunswick |
| XKX | Lehman Daimler |
| XKX | Lehman G E Capital |
| XL | X L Capital, LTD. |
| XLCP | U S X Capital Trust I |
| XLS | Exelis Inc. |
| XMM | Cross Media Marketing (delisted) |
| XNR | Xanser Corporation |
| XOM | Exxon Mobil Corporation |
| XPZ | U S X Capital Trust I |
| XRX | XEROX Corporation |
| XSB | Salomon Smith Barney Holdings I |
| XTO | XTO Energy Inc. (formerly Cross Timbers Oil Company) |
| XTOPA | Cross Timbers Oil Company Preferred A |
| XTR | XTRA Corporation |
| XTS | S B C Communications, Inc. |
| XVF | Lehman ABS Corporation |
| XVF | MediaOne Group, Inc. |
| XWC | World Wireless Communications |