| NINetbio INC | Waltham | MA | Computer and Electronic Product Manufacturing334516 | — | ◐ LIKELY ACTIVE |
| RFRaytheon Former Waltham Facil | Waltham | MA | Computer and Electronic Product Manufacturing334290 | — | ◐ LIKELY ACTIVE |
| HIHarvey Industries INC | Waltham | MA | Machinery Manufacturing333921 | — | ◐ LIKELY ACTIVE |
| QSQueen Screw & Mfg. INC. | Waltham | MA | Fabricated Metal Product Manufacturing332722 | 20-99 | ◐ LIKELY ACTIVE |
| AIArtisan Industries Incorporated | Waltham | MA | Chemical Manufacturing325412 | — | ◇ UNVERIFIED |
| BDBecton Dickinson & CO Acutecare | Waltham | MA | Miscellaneous Manufacturing339112 | — | ◇ UNVERIFIED |
| CWCcnne Waltham | Waltham | MA | Beverage and Tobacco Product Manufacturing312111 | — | ◇ UNVERIFIED |
| GDGenzyme Drug Discovery & Development | Waltham | MA | Chemical Manufacturing325412 | — | ◇ UNVERIFIED |
| LFLongview Fibre Company | Waltham | MA | Paper Manufacturing322220 | — | ◇ UNVERIFIED |
| NINanostone INC. | Waltham | MA | Machinery Manufacturing333310 | — | ◇ UNVERIFIED |
| PCPolaroid Corporation | Waltham | MA | Chemical Manufacturing325992 | — | ◇ UNVERIFIED |
| PPolaroid (former) | Waltham | MA | Chemical Manufacturing325992 | — | ◇ UNVERIFIED |
| RCRaytheon Company Mpt | Waltham | MA | Computer and Electronic Product Manufacturing334411 | — | ◇ UNVERIFIED |
| SSanofi | Waltham | MA | Chemical Manufacturing325411 | — | ◇ UNVERIFIED |
| STStandard Thomson CORP | Waltham | MA | Machinery Manufacturing333998 | — | ◇ UNVERIFIED |
| 2W283 - Waltham | Waltham | MA | Machinery Manufacturing333120 | 1-19 | ◐ LIKELY ACTIVE |
| AWAbcam Waltham | Waltham | MA | Chemical Manufacturing325413 | 100-499 | ◐ LIKELY ACTIVE |
| AIAnduril Industries, INC. | Waltham | MA | Computer and Electronic Product Manufacturing334511 | — | ◐ LIKELY ACTIVE |
| AIArdelyx, INC. | Waltham | MA | Chemical Manufacturing325412 | — | ◐ LIKELY ACTIVE |
| BBoston | Waltham | MA | Food Manufacturing311991 | 1-19 | ◐ LIKELY ACTIVE |
| BDBoston Dynamics, INC. | Waltham | MA | Machinery Manufacturing333998 | — | ▲ REPORTED CLOSED |
Dentsply Sirona Implants North America | Waltham | MA | Miscellaneous Manufacturing339116 | 100-499 | ◐ LIKELY ACTIVE |
| ETEntasis Therapeutics, INC. | Waltham | MA | Chemical Manufacturing325412 | — | ◐ LIKELY ACTIVE |
| ELEpifny LLC | Waltham | MA | Miscellaneous Manufacturing339113 | — | ◐ LIKELY ACTIVE |
| GAGeneral Atomics - GBM01 | Waltham | MA | Transportation Equipment Manufacturing336411 | 20-99 | ◐ LIKELY ACTIVE |
| GBGeneral Biological Corporation | Waltham | MA | Chemical Manufacturing325920 | — | ◐ LIKELY ACTIVE |
| IBIntrepid Battery LLC | Waltham | MA | Electrical Equipment, Appliance & Component Manufacturing335910 | — | ◐ LIKELY ACTIVE |
| IRItalian Ready Meals LLC | Waltham | MA | Food Manufacturing311612 | — | ◐ LIKELY ACTIVE |
| KLKura LLC | Waltham | MA | Beverage and Tobacco Product Manufacturing312130 | — | ◐ LIKELY ACTIVE |
| LRLam Research Corp Field Office | Waltham | MA | Machinery Manufacturing333242 | 20-99 | ◐ LIKELY ACTIVE |
| MSMighty Squirrel | Waltham | MA | Beverage and Tobacco Product Manufacturing312130 | — | ◐ LIKELY ACTIVE |
| MBMiltenyi Biotec Waltham | Waltham | MA | Chemical Manufacturing325412 | 100-499 | ◐ LIKELY ACTIVE |
| MTModerna, TX. - Waltham MTC | Waltham | MA | Chemical Manufacturing325414 | 1-19 | ◐ LIKELY ACTIVE |
| NENew England Charcuterie, LLC | Waltham | MA | Food Manufacturing311612 | — | ◐ LIKELY ACTIVE |
| QNQinetiq, NA Waltham | Waltham | MA | Computer and Electronic Product Manufacturing334511 | 20-99 | ◐ LIKELY ACTIVE |
| VSVB Spine Waltham | Waltham | MA | Miscellaneous Manufacturing339113 | 1-19 | ◐ LIKELY ACTIVE |
| VIVizgen, Inc. (Waltham) | Waltham | MA | Machinery Manufacturing333310 | 20-99 | ◐ LIKELY ACTIVE |
| WFWelch Foods, Inc. - Corporate | Waltham | MA | Food Manufacturing311421 | 100-499 | ◐ LIKELY ACTIVE |
| BMBoynton Machine Company INC | Waltham | MA | Machinery Manufacturing333318 | 1-19 | ◇ UNVERIFIED |
| CMClematis Machine and Fixture | Waltham | MA | Fabricated Metal Product Manufacturing332710 | 1-19 | ◇ UNVERIFIED |
| CLCounteredge, LLC | Waltham | MA | Nonmetallic Mineral Product Manufacturing327991 | 1-19 | ◇ UNVERIFIED |
| LELectro Engineering | Waltham | MA | Fabricated Metal Product Manufacturing332999 | 1-19 | ◇ UNVERIFIED |
| MIMarketwise Inc. | Waltham | MA | Furniture and Related Product Manufacturing337215 | 1-19 | ◇ UNVERIFIED |
| PCPrestige Custom Mirror & Glass, INC. | Waltham | MA | Nonmetallic Mineral Product Manufacturing327215 | 1-19 | ◇ UNVERIFIED |
| TITecogen INC | Waltham | MA | Machinery Manufacturing333415 | 20-99 | ◇ UNVERIFIED |
| 5W580 Winter Street LLC | Waltham | MA | Miscellaneous Manufacturing339999 | — | ◇ UNVERIFIED |
| AAllay | Waltham | MA | Beverage and Tobacco Product Manufacturing312130 | — | ◇ UNVERIFIED |
| ATAmide Technologies INC | Waltham | MA | Chemical Manufacturing325412 | — | ◇ UNVERIFIED |
| AIAvedro INC | Waltham | MA | Chemical Manufacturing325412 | — | ◇ UNVERIFIED |
| BPBbc Printing and Products INC | Waltham | MA | Printing and Related Support Activities323111 | — | ◇ UNVERIFIED |