| C.C.JENSEN A/S Denmark |
| Cadar Ltd United Kingdom |
| Camfil Farr Sweden |
| Carbis Filtration Ltd United Kingdom |
| Chemviron Carbon Belgium |
| Chemviron Carbon Cloth Division United Kingdom |
| Christ Water Technology Group Switzerland |
| Clark-Reliance United States |
| Clear Edge Filtration United States |
| Clearflow Environmental Technologies Ltd United Kingdom |
| Clyde Materials Handling Ltd Incorporating MAC Equipment United Kingdom |
| Cofasa Peru |
| Colbond bv Netherlands |
| CoMeTas DK Denmark |
| CREAT Sas France |
| Custom Filter LLC United States |