| MarJam Supply Company, Inc. PA | Retail Trade | 0 | — | D |
| Marjan Stone Inc. CA | Manufacturing | 0 | — | F |
| Mark A. Poley MI | Administrative & Waste Services | 0 | — | F |
| Mark Adams Greenhouses, Inc. NY | Wholesale Trade | 0 | — | A |
| Mark Andy Inc. MO | Transportation & Warehousing | 0 | — | A |
| Mark Ann Industries PA | Transportation & Warehousing | 0 | — | D |
| Mark Anthony Brewing NJ | Manufacturing | 0 | — | B |
| Mark Anthony Brewing SC | Manufacturing | 0 | — | B |
| Mark Anthony Brewing Company AZ | Manufacturing | 0 | — | A |
| Mark Anthony Services Inc. IL | Manufacturing | 1 | $182,000 | — |
| Mark Bauder Orchards WA | Agriculture & Forestry | 0 | — | D |
| Mark Beamish Waterproofing, Inc. CA | Construction | 0 | — | F |
| Mark C Pope Associates, Inc. GA | Manufacturing | 0 | — | A |
| Mark Carpenter Plumbing, Inc NM | Construction | 0 | — | F |
| Mark Cerrone Inc. NY | Construction | 0 | — | D |
| Mark David Levine, M.D., Professional Corporation CA | Healthcare & Social Assistance | 4 | $328,058 | — |
| Mark Former, M.D., P.C. and Mark Fromer LLC 6 NYC locations NY | — | 0 | — | — |
| MARK G. ANDERSON CONSULTANTS, INC. DC | Construction | 2 | $80,000 | — |
| Mark Haynes Construction, Inc. OH | Construction | 0 | — | F |
| Mark Hershey Farms, Inc. PA | Manufacturing | 0 | — | A |
| Mark III ID | — | 0 | — | — |
| Mark III Plant Construction, Ltd. TX | Construction | 0 | — | A |
| Mark Infotech Inc NJ | Professional & Technical Services | 4 | $112,800 | — |
| Mark IV Enterprises NY | Construction | 0 | — | F |
| Mark Lee And Yong Kay, Inc., D.B.A. Bay Construction Co CA | Construction | 0 | — | A |
| Mark Lee Excavating INC MN | Construction | 0 | — | F |
| Mark Linaweaver Hauling, LLC. LA | Transportation & Warehousing | 0 | — | A |
| Mark Line Industries IN | — | 0 | — | — |
| Mark Line Industries of Pennsylvania, LLC PA | — | 0 | — | — |
| MARK Logistics, LLC OK | Transportation & Warehousing | 0 | — | F |
| MARK MACHINE COMPANY NJ | — | 0 | — | — |
| Mark Magrann Associates, Inc. NJ | Professional & Technical Services | 1 | $74,818 | — |
| Mark Malone MDPA dba Advanced Pain Care TX | Healthcare & Social Assistance | 0 | — | A |
| Mark Mariani Inc. NY | Construction | 0 | — | A |
| Mark McKean Farms CA | Agriculture & Forestry | 0 | — | F |
| Mark Moses Electrical Services, Inc. PA | Construction | 0 | — | A |
| Mark of Honor Youth Lodge, Inc. NE | — | 0 | — | — |
| Mark One Electric MO | Construction | 0 | — | A |
| Mark Porter Auto Group-Mark Porter Autoplex, Inc. OH | — | 0 | — | — |
| Mark Porter Auto Group-Porter CDJR, Inc. OH | — | 0 | — | — |
| Mark Porter Auto Group-Porter Jackson, Inc. OH | — | 0 | — | — |
| Mark Richey Woodworking MA | Manufacturing | 0 | — | D |
| Mark Richey Woodworking and Design MA | Manufacturing | 0 | — | F |
| Mark Rite Lines MT | Manufacturing | 0 | — | F |
| Mark Rite Lines Equipment Company MT | Construction | 0 | — | F |
| Mark Rite Lines/ High Mark MT | Manufacturing | 0 | — | F |
| Mark Sand & Gravel Co. MN | Construction | 0 | — | D |
| Mark Schaffer Excavating & Trucking, Inc. OH | Construction | 0 | — | A |
| Mark Spaulding Construction Company KY | Construction | 0 | — | A |
| Mark Spencer Hotel OR | Accommodation & Food Services | 0 | — | A |
