| Carfax | Centreville | 1984 |
| Carhartt | Dearborn | 1889 |
| Carlson Wagonlit Travel | Minneapolis | 1994 |
| Carlyle Group | Washington, D.C. | 1987 |
| Carrier Global | Farmington | 26 de junho de 1915 |
| CBRE, Inc. | Dallas, Los Angeles | 1906 |
| CBS Corporation | CBS Building | 30 de novembro de 1997 |
| CBS Radio | Nova Iorque | 1928 |
| Cedar Fair | Sandusky | 1983 |
| Celgene | Summit | 1986 |
| Cengage Learning | Stamford | 2000 |
| Century 21 Real Estate | Madison | 1971 |
| Cerberus Capital Management | Nova Iorque | 1992 |
| CF Industries | Deerfield, Deerfield | 1946 |
| CH2M Hill | Meridian | 1946 |
| Champ Car | — | 1979 |
| Chaosium | Hayward, Albany | 31 de outubro de 1975 |
| Chemical Bank | Midland, Nova Iorque | 1954 |
| Chicago Mercantile Exchange | Chicago | 1898 |
| Chikara | Filadélfia | 2002 |
| Chips and Technologies | Milpitas | 1985 |
| Chobani | Norwich | 2005 |
| Choice Hotels | Rockville, Silver Spring | 1939 |
| Church & Dwight | Ewing | 1846 |
| Circle | Boston | outubro 2013 |
| CIT Group Incorporated | Nova Iorque | 1908 |
| Citadel Enterprise Americas LLC | Miami | 1990 |
| Citibank | Sioux Falls, Nova Iorque | 1865 |
| Citigroup | 388 Greenwich Street | 8 de outubro de 1998 |
| Citrix Systems | Fort Lauderdale | 1989 |
| Claris | Cupertino | 1987 |
| Coda Automotive | Los Angeles | 2009 |
| Cognex Corporation | Natick | 1981 |
| Coinbase | São Francisco | 20 de junho de 2012 |
| Coldwell Banker | Cairo, Madison | 27 de agosto de 1906 |
| Cole Haan | Greenland | 1928 |
| Coleco | West Hartford | 1932 |
| Coleman (marca) | Wichita | 1900 |
| Color Force | West Hollywood | 2007 |
| Colt's Manufacturing Company | West Hartford | 1855 |
| Columbia Sportswear | Cedar Mill | 1938 |
| Comerica | Dallas | 1849 |
| Commodore International | West Chester | 10 de outubro de 1958 |
| Commonwealth Fusion Systems | Devens | 2018 |
| Compaq | Houston | 16 de fevereiro de 1982 |
| Complex | Nova Iorque | 2002 |
| Compuserve | Columbus | 1969 |
| Concord Music | Beverly Hills | 1973 |