| MASTERCRAFT TOOL & MACHINE CO., INC CT | Manufacturing | 0 | — | F |
| MASTERCUT TOOL CORPORATION FL | Manufacturing | 0 | — | F |
| Masterduct, Inc. TX | Manufacturing | 0 | — | F |
| Masterflex LLC IL | Manufacturing | 0 | — | F |
| Masterflex Part Of Avantor IL | Manufacturing | 0 | — | A |
| Mastergrind EDM II NY | Manufacturing | 0 | — | A |
| Masterguard IN | Manufacturing | 0 | — | F |
| MasterHand Milling NE | Manufacturing | 0 | — | F |
| Masterhand Milling OK | Manufacturing | 0 | — | F |
| Mastermelt America TN | Manufacturing | 0 | — | A |
| Mastermelt Conecsus Aero TX | Manufacturing | 0 | — | F |
| MasterMold WI | Manufacturing | 0 | — | F |
| Mastermolding Plastics LLC IL | Manufacturing | 0 | — | A |
| MASTERPIECE ART GALLERY CA | — | 0 | — | — |
| Masters Bros, Inc. IL | Construction | 0 | — | A |
| MASTERS BUILDING SOLUTIONS WI | Construction | 0 | — | A |
| Masters Company, Inc IL | Manufacturing | 0 | — | A |
| Masters Concrete Products PA | Manufacturing | 0 | — | F |
| Masters Electric Inc MD | Construction | 0 | — | A |
| Masters Electrical Services LTD. TX | Construction | 0 | — | D |
| Masters Gallery Foods, Inc. WI | Wholesale Trade | 0 | — | D |
| Masters Heating & Cooling, Inc. IN | Construction | 0 | — | F |
| Masters Logistics LLC CA | Transportation & Warehousing | 0 | — | D |
| Masters Machine Company Inc. ME | Manufacturing | 0 | — | F |
| MASTERS MANAGEMENT LLC PA | Administrative & Waste Services | 0 | — | D |
| Masters RMC, Inc. PA | Manufacturing | 0 | — | F |
| Masters Surfacing Technology. Inc. CA | Construction | 0 | — | A |
| Masters Transport & Logistics, LLC TX | Transportation & Warehousing | 0 | — | F |
| MasterScapes Inc. TX | Administrative & Waste Services | 0 | — | C |
| Masterson Company WI | Manufacturing | 0 | — | F |
| Masterson Staffing Solutions, Inc. MN | Administrative & Waste Services | 0 | — | A |
| MasterTech Inc MO | Construction | 0 | — | F |
| Masthead Holdings LLC OH | Wholesale Trade | 0 | — | A |
| Masthead International Inc. AZ | Construction | 0 | — | A |
| Mastria Buick, GMC, Cadillac MA | Retail Trade | 0 | — | A |
| Mastria Kia MA | Retail Trade | 0 | — | A |
| Mastria Nissan MA | Retail Trade | 0 | — | A |
| Mastria Subaru MA | Retail Trade | 0 | — | C |
| Mastria Volkswagen MA | Retail Trade | 0 | — | A |
| Mastro Services Inc TX | Professional & Technical Services | 6 | $88,819 | — |
| Mastroianni Bros, Inc. NY | — | 0 | — | — |
| Mastroianni Family Enterprises dba Jay's Catering & Ellie's Table CA | — | 0 | — | — |
| Mastronardi CA | Wholesale Trade | 0 | — | A |
| MASTRONARDI MOREHEAD INC KY | Agriculture & Forestry | 0 | — | B |
| Mastronardi Produce FL | Transportation & Warehousing | 0 | — | A |
| Mastronardi Produce MI | Transportation & Warehousing | 0 | — | A |
| Mastronardi Produce OH | Agriculture & Forestry | 0 | — | A |
| MASTRONARDI PRODUCE PA | Transportation & Warehousing | 0 | — | A |
| Mastronardi Produce UT | Agriculture & Forestry | 0 | — | C |
| Mastronardi Produce - USA, Inc. MI | Transportation & Warehousing | 1 | $150,000 | — |
