| Year | Detail |
| 1939 |
Northrop Aircraft Inc. was founded. |
| 1994 |
Grumman Corp. got merged with Northrop. |
| 1996 |
Westinghouse Electric Corp. was acquired by the company. |
| 1997 |
The company acquired Logicon Corp. |
| 1999 |
The company acquired Teledyne Ryan Aeronautical. |
| 2001 |
The company acquired Litton Industries. |
| 2002 |
The company acquired TRW Inc. |
| 2007 |
The company acquired Scaled Composites. |
| 2018 |
The company acquired Orbital ATK. |
| 2023 |
Northrop Grumman and LIG Nex1 collaborated on electronic warfare systems for Korea. |
| 2024 |
Northrop Grumman and EpiSci collaborated on advanced autonomy capabilities. |