| SIC Code | Business or Product | Registrants |
|---|
|  | | |
| 3841 | Clamps, surgical | 654 |
| 0913 | Clams, digging of | * |
| 3532 | Clarifying machinery, mineral | 13 |
| 3931 | Clarinets and parts | 10 |
| 3131 | Clasps, shoe | * |
| 7929 | Classical music groups or artists | * |
| 3532 | Classifiers, metallurgical and mining | 13 |
| 2631 | Clay coated board – made in the same establishment | 29 |
| 5032 | Clay construction materials, except refractory – wholesale | * |
| 3295 | Clay for petroleum refining, chemically processed | * |
| 3255 | Clay refractories | * |
| 3295 | Clay, ground or otherwise treated | * |
| 1459 | Clays (common) quarrying-not in conjunction with manufacturing | * |
| 3559 | Clayworking and tempering machines | 141 |
| 7218 | Clean room apparel supply service | * |
| 1541 | Clean room construction-general contractors | * |
| 3714 | Cleaners, air: motor vehicle | 366 |
| 3599 | Cleaners, boiler tube | * |
| 3999 | Cleaners, pipe and cigarette holder | * |
| 3471 | Cleaning and descaling metal products, for the trade | * |
________
* There are SEC Registrants, but only at the 2- or 3-digit SIC Code levels. |
