| AAAerospace Avionics INC | Ronkonkoma | — | ◐ LIKELY ACTIVE |
| TCTelephonics Corporation | Huntington | — | ◇ UNVERIFIED |
American Aerospace Controls INC | Farmingdale | — | ◐ LIKELY ACTIVE |
Brightwaters Instrument CORP | Brightwaters | — | ◐ LIKELY ACTIVE |
Display Logic USA INC | Hauppauge | — | ◐ LIKELY ACTIVE |
Powertek US INC | Holbrook | — | ◐ LIKELY ACTIVE |
| BSBae Systems Information and Electronic Systems Integration INC. | Greenlawn | — | ◐ LIKELY ACTIVE |
| BABig Apple Sign CORP | Islandia | — | ◐ LIKELY ACTIVE |
| PIPeerless Instrument Co., INC. | Farmingdale | — | ◐ LIKELY ACTIVE |
| WUWidex USA INC | Hauppauge | — | ◐ LIKELY ACTIVE |
| 1P100 Pine Aire Drive | Bay Shore | — | ◇ UNVERIFIED |
| APaction Anodizing & Plating & Polishing CORP Superfund Site | Copiague | — | ◇ UNVERIFIED |
| ATAmerican Technical Ceramics | Huntington Station | — | ◇ UNVERIFIED |
| ACAnorad CORP. | Hauppauge | — | ◇ UNVERIFIED |
| ELEdo LLC a Wholly Owned Subsidiary of Harris CORP | Bohemia | — | ◇ UNVERIFIED |
| HDHome Depot #1285 | Deer Park | — | ◇ UNVERIFIED |
| ITIntegrated Technology Lab INC | Deer Park | — | ◇ UNVERIFIED |
| ICItt CORP | North Amityville | — | ◇ UNVERIFIED |
| LNL-3 Narda-atm | Patchogue | — | ◇ UNVERIFIED |
| MCMicrowave Circuit Technology INC | Farmingdale | — | ◇ UNVERIFIED |
| PHParker Hannifin CORP Fluid Systems Division | Smithtown | — | ◇ UNVERIFIED |
| RSR S M Electron Power INC | Deer Park | — | ◇ UNVERIFIED |
| SSSedco Systems INC | Melville | — | ◇ UNVERIFIED |
| STSymbol Technologies | Holtsville | — | ◇ UNVERIFIED |
| TOTellabs Ops INC | Ronkonkoma | — | ◇ UNVERIFIED |
| VIVacuum Instruments Corporation LLC | Ronkonkoma | — | ◇ UNVERIFIED |
| VSVenus Scientific INC | Farmingdale | — | ◇ UNVERIFIED |
| CSCentral Semiconductor, LLC | Hauppauge | 20–99 | ◐ LIKELY ACTIVE |
| CUChyronhego US Holding Corporation | Melville | — | ◐ LIKELY ACTIVE |
| DBDDC - Bohemia | Bohemia | 100–499 | ◐ LIKELY ACTIVE |
| EBEquilibrated Bio Systems, INC. | Smithtown | — | ◐ LIKELY ACTIVE |
| FTFrontgrade Technologies, Inc. Hauppague | Hauppague | 20–99 | ◐ LIKELY ACTIVE |
| GCGeo Calibration INC | Ronkonkoma | — | ◐ LIKELY ACTIVE |
| ITIntegrated Technology Lab, INC. | Bay Shore | — | ◐ LIKELY ACTIVE |
| IDIsland Designers Associates, INC. | Holbrook | — | ◐ LIKELY ACTIVE |
| IRIsland Research and Development Corporation | Ronkonkoma | — | ◐ LIKELY ACTIVE |
| MIMetris Instruments_east, LLC | South Setauket | — | ◐ LIKELY ACTIVE |
| MTMicrochip Technology Inc. Hauppauge | Hauppauge | 100–499 | ◐ LIKELY ACTIVE |
| MPMini-Circuits (Deer Park) | Deer Park | 20–99 | ◐ LIKELY ACTIVE |
| MEMkc Electronics INC | Holbrook | — | ◐ LIKELY ACTIVE |
| MSMotorola Solutions Inc. | Bay Shore | 1–19 | ◐ LIKELY ACTIVE |
| NCNic Components CORP | Melville | — | ◐ LIKELY ACTIVE |
| NANy193 Ametek Magnetrol Usa, LLC | Edgewood | 20–99 | ◐ LIKELY ACTIVE |
| OSOmnia Semiconductor INC | Babylon | — | ◐ LIKELY ACTIVE |
| OBOptel Business Communication Systems, INC. | Smithtown | — | ◐ LIKELY ACTIVE |
| PBPDC - Bohemia | Bohemia | 100–499 | ◐ LIKELY ACTIVE |
| PIPetrex International, INC. | Commack | — | ◐ LIKELY ACTIVE |
| PNPluritec, North America, LTD. | Bohemia | — | ◐ LIKELY ACTIVE |
| PIProtronics INC | Wading River | — | ◐ LIKELY ACTIVE |
| SHSag Harbor Industries New York | Sag Harbor | 20–99 | ◐ LIKELY ACTIVE |