| 2610 | Insulators, electrical, glass, made in glass making plants | |
| 2610 | Insulators, electrical, made from purchased glass | |
| 5150 | Insulators, electrical, wholesale | |
| 3190 | Insulators, hard rubber, manufacturing (electric) | |
| 2423 | Insulin preparations, manufacturing | |
| 2423 | Insulin, uncompounded, manufacturing | |
| 6720 | Insurance adjusters | |
| 6720 | Insurance advisory services | |
| 6720 | Insurance agency | |
| 6720 | Insurance agents | |
| 6720 | Insurance agents and brokers | |
| 9111 | Insurance association | |
| 6720 | Insurance broker services | |
| 6720 | Insurance brokers and consultants | |
| 7010 | Insurance buildings, operation of | |
| 6603 | Insurance carriers, accident | |
| 6603 | Insurance carriers, fire, marine and casualty | |
| 6603 | Insurance carriers, health | |
| 6601 | Insurance carriers, life | |
| 6720 | Insurance claim adjusters | |
| 6720 | Insurance commercial, agents and brokers | |
| 7513 | Insurance commission, federal government | |
| 6720 | Insurance consultants | |
| 6720 | Insurance educational services | |
| 6720 | Insurance information bureaus | |
| 6720 | Insurance inspection and investigation (except claims investigation), services | |
| 6720 | Insurance inspectors and adjusters | |
| 6720 | Insurance loss prevention services | |
| 6720 | Insurance office, agents and brokers | |
| 8519 | Insurance physical examination service (except by physicians) | |
| 6720 | Insurance professional standards services | |
| 6720 | Insurance rate making services | |
| 6720 | Insurance reporting services | |
| 6720 | Insurance research services | |
| 6720 | Insurance sales and service, agents and brokers | |
| 6720 | Insurance services | |
| 6603 | Insurance underwriters, fire | |
| 6601 | Insurance underwriters, life | |
| 6603 | Insurance, accident and health | |
| 6603 | Insurance, bank deposit or share | |