| STSilicon Transistor C | Chelmsford | MA | Computer and Electronic Product Manufacturing334413 | — | ◇ UNVERIFIED |
| STSimplex Time Recorder CO -tyco Safety Products | Westminster | MA | Computer and Electronic Product Manufacturing334290 | — | ◇ UNVERIFIED |
| SCSipex Corporation | Billerica | MA | Computer and Electronic Product Manufacturing334419 | — | ◇ UNVERIFIED |
| SVSloan Valve Arichell Technologies Div | West Newton | MA | Computer and Electronic Product Manufacturing334412 | — | ◇ UNVERIFIED |
| TFTeledyne Flir Surveillance INC | N. Billerica | MA | Computer and Electronic Product Manufacturing334511 | — | ◇ UNVERIFIED |
| TPTeledyne Philbrick | Dedham | MA | Computer and Electronic Product Manufacturing334413 | — | ◇ UNVERIFIED |
| TPTitan Pcb East INC | Amesbury | MA | Computer and Electronic Product Manufacturing334412 | — | ◇ UNVERIFIED |
| TETrombetta Electronics | Malden | MA | Computer and Electronic Product Manufacturing334419 | — | ◇ UNVERIFIED |
| TETyco Electronics | North Attleboro | MA | Computer and Electronic Product Manufacturing334417 | — | ◇ UNVERIFIED |
| TETyco Electronics | Burlington | MA | Computer and Electronic Product Manufacturing334220 | — | ◇ UNVERIFIED |
| TETyco Electronics | Norwood | MA | Computer and Electronic Product Manufacturing334417 | — | ◇ UNVERIFIED |
| TCTympanium Corporation | Malden | MA | Computer and Electronic Product Manufacturing334419 | — | ◇ UNVERIFIED |
| UUltra | Braintree | MA | Computer and Electronic Product Manufacturing334511 | — | ◇ UNVERIFIED |
| UMUltra Maritime Naval Systems and Sensors | Quincy | MA | Computer and Electronic Product Manufacturing334511 | — | ◇ UNVERIFIED |
| WRWellesley Rosewood Maynard Mills | Maynard | MA | Computer and Electronic Product Manufacturing334411 | — | ◇ UNVERIFIED |
| WRWyeth Research | Cambridge | MA | Computer and Electronic Product Manufacturing334516 | — | ◇ UNVERIFIED |
| 1C109 Constitution Franklin MA | Franklin | MA | Computer and Electronic Product Manufacturing334112 | 20-99 | ◐ LIKELY ACTIVE |
| 1S125 Summer Street Boston, MA | Boston | MA | Computer and Electronic Product Manufacturing334413 | 100-499 | ◐ LIKELY ACTIVE |
| 1A1 Analog Way | Wilmington | MA | Computer and Electronic Product Manufacturing334413 | 500+ | ◐ LIKELY ACTIVE |
| 2A20 Alpha Rd. Chelmsford, MA | Chelmsford | MA | Computer and Electronic Product Manufacturing334413 | 100-499 | ◐ LIKELY ACTIVE |
| 2E2 Elizabeth | Chelmsford | MA | Computer and Electronic Product Manufacturing334413 | 100-499 | ◐ LIKELY ACTIVE |
| 9H908 Hq | Burlington | MA | Computer and Electronic Product Manufacturing334516 | 100-499 | ◐ LIKELY ACTIVE |
| ACAccuprobe CORP | Salem | MA | Computer and Electronic Product Manufacturing334515 | — | ◐ LIKELY ACTIVE |
| AHAccure Health INC | Cambridge | MA | Computer and Electronic Product Manufacturing334516 | — | ◐ LIKELY ACTIVE |
| ASAdaptas Solutions, LLC | Palmer | MA | Computer and Electronic Product Manufacturing334516 | — | ◐ LIKELY ACTIVE |
| ASAmerican Superconductor Corporation- Westminster, Massachusetts | Westminster | MA | Computer and Electronic Product Manufacturing334511 | 20-99 | ◐ LIKELY ACTIVE |
| APAmphenol PCD | Beverly, United States | MA | Computer and Electronic Product Manufacturing334417 | 100-499 | ◐ LIKELY ACTIVE |
| APAmphenol Pcd INC | Beverly | MA | Computer and Electronic Product Manufacturing334417 | — | ▲ REPORTED CLOSED |
| AIAmplified Industries, INC. | Boston | MA | Computer and Electronic Product Manufacturing334513 | — | ◐ LIKELY ACTIVE |
| ATAndor Technology, INC. | Concord | MA | Computer and Electronic Product Manufacturing334516 | — | ▲ REPORTED CLOSED |
| AAndover | Andover | MA | Computer and Electronic Product Manufacturing334413 | 100-499 | ◐ LIKELY ACTIVE |
| AFAndover Facility HQ | Andover | MA | Computer and Electronic Product Manufacturing334111 | 100-499 | ◐ LIKELY ACTIVE |
| AIAnduril Industries, INC. | Waltham | MA | Computer and Electronic Product Manufacturing334511 | — | ◐ LIKELY ACTIVE |
| ANApplied Nanofemto Technologies LLC | Lowell | MA | Computer and Electronic Product Manufacturing334413 | — | ▲ REPORTED CLOSED |
| ALAutonodyne LLC | Boston | MA | Computer and Electronic Product Manufacturing334511 | — | ◐ LIKELY ACTIVE |
Aved Electronics, LLC | Lowell | MA | Computer and Electronic Product Manufacturing334419 | — | ◐ LIKELY ACTIVE |
| ATAxiom Technology, INC U.s.a | Methuen | MA | Computer and Electronic Product Manufacturing334118 | — | ◐ LIKELY ACTIVE |
| BSBAE Systems Electronic Systems LEX | Lexington | MA | Computer and Electronic Product Manufacturing334419 | 20-99 | ◐ LIKELY ACTIVE |
| BSBionet Sonar, INC. | Burlington | MA | Computer and Electronic Product Manufacturing334220 | — | ◐ LIKELY ACTIVE |
| BNBms Nat | Cambridge | MA | Computer and Electronic Product Manufacturing334516 | 1-19 | ◐ LIKELY ACTIVE |
| BBoston | Marlborough | MA | Computer and Electronic Product Manufacturing334413 | 1-19 | ◐ LIKELY ACTIVE |
| BOBoston Office (NAT) | Marlborough | MA | Computer and Electronic Product Manufacturing334516 | 20-99 | ◐ LIKELY ACTIVE |
Bruker BioSpin Corporation - Southborough | Southborough | MA | Computer and Electronic Product Manufacturing334516 | 1-19 | ◐ LIKELY ACTIVE |
| CWCanton Warehouse | Canton | MA | Computer and Electronic Product Manufacturing334516 | 1-19 | ◐ LIKELY ACTIVE |
| CICerebloom, INC. | Belmont | MA | Computer and Electronic Product Manufacturing334510 | — | ◐ LIKELY ACTIVE |
| CAChasm Advanced Materials, Inc. - Canton | Canton | MA | Computer and Electronic Product Manufacturing334412 | 1-19 | ◐ LIKELY ACTIVE |
| CHChelsea Holdings Group INC | Chelsea | MA | Computer and Electronic Product Manufacturing334519 | — | ◐ LIKELY ACTIVE |
| C7Chicopee 711 | Chicopee | MA | Computer and Electronic Product Manufacturing334516 | 20-99 | ◐ LIKELY ACTIVE |
| CICircuithub, INC | S Deerfield | MA | Computer and Electronic Product Manufacturing334418 | — | ◐ LIKELY ACTIVE |
| CICircuithub, INC | S. Deerfield | MA | Computer and Electronic Product Manufacturing334418 | — | ◐ LIKELY ACTIVE |