| Jacuzzi | Chino Hills | 1917 |
| Jamba Juice | Frisco | 1990 |
| JBL | Northridge | 1946 |
| Jeep | Toledo | 1941 |
| Jelly Belly Candy Company | Fairfield | 1898 |
| Jet | — | — |
| Jim Crockett Promotions | Charlotte | 1931 |
| John Broadwood and Sons Limited | Nova Iorque, Londres | 1732 |
| John Hancock Insurance | Boston | 1862 |
| Johns-Manville | Denver | 1858 |
| Johnson & Johnson | New Brunswick | 1886 |
| JPMorgan Chase | Nova Iorque | 1968 |
| Juul | São Francisco | julho 2017 |
| K-Swiss | Westlake Village | 1966 |
| Kaggle | São Francisco | abril 2010 |
| Kaiser Permanente | Oakland | 1945 |
| Kaltura | Nova Iorque, Nova Iorque | 2006 |
| Kaplan International Languages | Londres | 1967 |
| Keds | Rockford | 1916 |
| Kel-Tec | Cocoa | 1991 |
| Kelvinator | — | 1914 |
| Kenner Products | Cincinnati | 1946 |
| KeyBank | Cleveland | 1825 |
| Keysight | Santa Rosa | 2014 |
| Kimberly-Clark | Irving | 1928 |
| King of the Cage | Rancho Cucamonga | 1998 |
| Kirby Company | Cleveland | 1914 |
| Kleiner Perkins | Menlo Park | 1972 |
| Kmart | Detroit | 1962 |
| Knoll | East Greenville | 1938 |
| Koch Industries | Wichita | 1940 |
| Kohler Company | Kohler | 6 de dezembro de 1873 |
| Kohl´s | Menomonee Falls | 1962 |
| Kraft Heinz Company | Pittsburgh | 2015 |
| Kumon | Osaka | 1958 |
| La Senza | Montreal | 1990 |
| Landmark Worldwide | São Francisco | 1991 |
| Lear Corporation | Southfield | 1917 |
| Lee | Kansas, Merriam | 1889 |
| Lehman Brothers | Nova Iorque | 1850 |
| Levi Strauss & Co. | São Francisco, Levi's Plaza | 1853 |
| Lexicon | Woodbury | 1971 |
| Lime | San Mateo | janeiro 2017 |
| Linden Lab | São Francisco | 1999 |
| Line 6 | Calabasas | 1996 |
| Lionel Corporation | Nova Iorque | 1900 |
| Lionsgate | Santa Mônica | 28 de abril de 1997 |
| Litton Industries | Milwaukee | 1953 |