| Abbreviation | Definition |
|---|---|
| NIPSN | Northern Industries Public Service Company (de-listed) |
| NIPSN | Northern Industries Public Service Company (de-listed) |
| NIPSO | Northern Industries Public Service Company |
| NIPSO | Northern Industries Public Service Company (de-listed) |
| NIPSO | Northern Industries Public Service Company (de-listed) |
| NIPSP | Northern Industries Public Service Company Preferred |
| NIPSP | Northern Industries Public Service Company Preferred (de-listed) |
| NIPSP | Northern Industries Public Service Company Preferred (de-listed) |
| NITE | Knight Trimark Group, Inc. |
| NJMC | New Jersey Mining Company |
| NKCIF | NewKidco International, Inc. |
| NKID | Noodle Kidoodle, Inc. |
| NKOT | Nu Kote Holdings, Inc. |
| NKSH | National Bankshares, Inc. |
| NKSH | National Bankshares, Inc., of Virginia |
| NLAB | NuOncology Labs, Inc. |
| NLBC | L. B. Nelson Corporation |
| NLCI | Nobel Learning Communities |
| NLCS | National Computer Systems, Inc. |
| NLMC | North Lily Mining Company |