| Abbreviation | Definition |
|---|---|
| DEGX | Mississippi Power |
| DEGX | Mississippi Power Company |
| DEMX | Demeter |
| DEMX | Demeter Incorporated |
| DEPX | Dependable Properties |
| DER | Dunn-Erwin Railway Corporation |
| DETX | Detroit Edison |
| DETX | Detroit Edison Company |
| DFSU | Dong Fang International Investment |
| DFSU | Dong Fang International Investment Limited |
| DFSZ | Dong Fang International Investment |
| DFSZ | Dong Fang International Investment Limited |
| DFTX | DTE Transportation Services |
| DGBY | Digby Truck Lines |
| DGBY | Digby Trucklines |
| DGCX | Dakota Gasification |
| DGCX | Dakota Gasification Company |
| DGHX | North American Chemical |
| DGIX | D and G Enterprises |
| DGNO | Dallas Garland and Northeastern Railroad Incorporated |