| CBS Corporation | CBS Building | 30 de novembro de 1997 |
| CBS Radio | Nova Iorque | 1928 |
| Cedar Fair | Sandusky | 1983 |
| Celanese Corporation | Irving | 1999 |
| Celera Corporation | Rockville, Alameda | maio 1998 |
| Cengage Learning | Stamford | 2000 |
| Century 21 Real Estate | Madison | 1971 |
| Cerberus Capital Management | Nova Iorque | 1992 |
| Cerebras Systems | Sunnyvale, São Francisco | 2016 |
| CH2M Hill | Meridian | 1946 |
| Champ Car | — | 1979 |
| Charter Arms | Shelton | 1964 |
| Chicago Board of Trade | Chicago | 1848 |
| Chicago, Rock Island and Pacific Railroad | Chicago | 1866 |
| Chipotle Mexican Grill | Denver, Newport Beach | 13 de julho de 1993 |
| Chobani | Norwich | 2005 |
| Choice Hotels | Rockville, Silver Spring | 1939 |
| Circle | Boston | outubro 2013 |
| Circuit City | Richmond | 1984 |
| Citadel Enterprise Americas LLC | Miami | 1990 |
| Citizens Financial Group | Providence | 1954 |
| Citrix Systems | Fort Lauderdale | 1989 |
| Claris | Cupertino | 1987 |
| Clinique | Nova Iorque | 1968 |
| Coda Automotive | Los Angeles | 2009 |
| Codecademy | Nova Iorque | 2011 |
| CodeGear | Scotts Valley, Califórnia | 2006 |
| Coldwell Banker | Cairo, Madison | 27 de agosto de 1906 |
| Colgate-Palmolive | Nova Iorque | 1806 |
| Color Force | West Hollywood | 2007 |
| Colorado Fuel and Iron | Colorado | — |
| Columbia Sportswear | Cedar Mill | 1938 |
| Combustion Engineering | Stamford | 1912 |
| Comcast | Filadélfia | 28 de junho de 1963 |
| Commodore International | West Chester | 10 de outubro de 1958 |
| Commonwealth Fusion Systems | Devens | 2018 |
| CommScope | Claremont | 1976 |
| Compuserve | Columbus | 1969 |
| Conair | East Windsor Township | 1959 |
| Concentrix | Fremont | 2004 |
| Conexant | Irvine | 1999 |
| Conn-Selmer | Elkhart | 1909 |
| Consol Energy | Pittsburgh | 1991 |
| Consolidated Aircraft | San Diego | 1923 |
| Consolidated Edison | Manhattan | 1 de janeiro de 1998 |
| Converse | Boston | 1910 |
| Cooper Tire & Rubber Company | Findlay | 1926 |
| Cord Automobile | Estados Unidos | 1929 |