| WGWienerberger Group (general Shale) | Beltsville | MD | Nonmetallic Mineral Product Manufacturing327120 | — | ◇ UNVERIFIED |
| YBYork Building Products - Cockeysville | Cockeysville | MD | Nonmetallic Mineral Product Manufacturing327331 | — | ◇ UNVERIFIED |
| AIAmerican Insulated Glass LLC - Baltimore | Ijamsville | MD | Nonmetallic Mineral Product Manufacturing327215 | 20-99 | ▲ REPORTED CLOSED |
| BRBay Ready Mix of Maryland Llc | Baltimore | MD | Nonmetallic Mineral Product Manufacturing327320 | 20-99 | ◐ LIKELY ACTIVE |
| BPBryantown Plant | Waldorf | MD | Nonmetallic Mineral Product Manufacturing327320 | 20-99 | ◐ LIKELY ACTIVE |
| CCrofton | Crofton | MD | Nonmetallic Mineral Product Manufacturing327331 | 20-99 | ◐ LIKELY ACTIVE |
| CSC.R. Semler Inc | Smithsburg, Md | MD | Nonmetallic Mineral Product Manufacturing327390 | 20-99 | ◐ LIKELY ACTIVE |
| GPGillespie Precast - Plant 2 | Chestertown | MD | Nonmetallic Mineral Product Manufacturing327390 | 100-499 | ◐ LIKELY ACTIVE |
| GBGold Bond Building Products - Baltimore | Baltimore | MD | Nonmetallic Mineral Product Manufacturing327420 | 100-499 | ◐ LIKELY ACTIVE |
| LPLexington Park Plant | Lexington Park | MD | Nonmetallic Mineral Product Manufacturing327320 | 1-19 | ◐ LIKELY ACTIVE |
| MLMaryland Laurel Gorman Road | Laurel | MD | Nonmetallic Mineral Product Manufacturing327991 | 20-99 | ◐ LIKELY ACTIVE |
| MCMiddle Concrete and Trucking, INC. | Brandywine | MD | Nonmetallic Mineral Product Manufacturing327320 | — | ◐ LIKELY ACTIVE |
| MSMR Stone, LLC | Monrovia | MD | Nonmetallic Mineral Product Manufacturing327991 | 20-99 | ◐ LIKELY ACTIVE |
| OHODL - Hagerstown, MD | Hagerstown | MD | Nonmetallic Mineral Product Manufacturing327215 | 1-19 | ◐ LIKELY ACTIVE |
| PSPowercon South | Odenton | MD | Nonmetallic Mineral Product Manufacturing327110 | 20-99 | ◐ LIKELY ACTIVE |
| PFProform Finishing Products - Belcamp | Belcamp | MD | Nonmetallic Mineral Product Manufacturing327420 | 20-99 | ◐ LIKELY ACTIVE |
| RRRocky Ridge Plant | Rocky Ridge | MD | Nonmetallic Mineral Product Manufacturing327120 | 20-99 | ◐ LIKELY ACTIVE |
| SRSchuster Ready Mix, LLC | Owings Mills | MD | Nonmetallic Mineral Product Manufacturing327320 | 100-499 | ◐ LIKELY ACTIVE |
| UPUnited Plate Glass Company (Frederick) | Frederick | MD | Nonmetallic Mineral Product Manufacturing327215 | 1-19 | ◐ LIKELY ACTIVE |
| WWilliamsport | Williamsport | MD | Nonmetallic Mineral Product Manufacturing327212 | 20-99 | ◐ LIKELY ACTIVE |
| SLStolzle Lausitz INC | Linthicum Heights | MD | Nonmetallic Mineral Product Manufacturing327212 | — | ◐ LIKELY ACTIVE |
| AIAdvent Industries LLC T a Mt Savage Firebrick | Frostburg | MD | Nonmetallic Mineral Product Manufacturing327124 | 20-99 | ◇ UNVERIFIED |
| AIAtlantic Imprints, Inc. | Baltimore | MD | Nonmetallic Mineral Product Manufacturing327215 | 20-99 | ◇ UNVERIFIED |
| CPCladdagh Pottery, Inc. | Annapolis | MD | Nonmetallic Mineral Product Manufacturing327112 | 1-19 | ◇ UNVERIFIED |
| CCCumberland Concrete Corporation | Lavale | MD | Nonmetallic Mineral Product Manufacturing327310 | 1-19 | ◇ UNVERIFIED |
| GIGranix INC | Laurel | MD | Nonmetallic Mineral Product Manufacturing327120 | 1-19 | ◇ UNVERIFIED |
| MSMaryland Style Marble & Granite, INC | Edgewater | MD | Nonmetallic Mineral Product Manufacturing327991 | 1-19 | ◇ UNVERIFIED |
| TCTgc Corporation | Millington | MD | Nonmetallic Mineral Product Manufacturing327331 | 1-19 | ◇ UNVERIFIED |
| 1W1501 W. Patapsco, LLC | Baltimore | MD | Nonmetallic Mineral Product Manufacturing327310 | — | ◇ UNVERIFIED |
| 2O2 Oceans Enterprises LLC | Gaithersburg | MD | Nonmetallic Mineral Product Manufacturing327211 | — | ◇ UNVERIFIED |
| AMAllan Myers Materials-jessup (rap) | Jessup | MD | Nonmetallic Mineral Product Manufacturing327999 | — | ◇ UNVERIFIED |
| AGAmerican Granite & Tile INC | Bishopville | MD | Nonmetallic Mineral Product Manufacturing327991 | — | ◇ UNVERIFIED |
| AGAmerica's Granite INC. | Rockville | MD | Nonmetallic Mineral Product Manufacturing327991 | — | ◇ UNVERIFIED |
| BCBeltway Custom Cultured Marble, INC. | Whiteford | MD | Nonmetallic Mineral Product Manufacturing327991 | — | ◇ UNVERIFIED |
| CGCapital Glass INC | Beltsville | MD | Nonmetallic Mineral Product Manufacturing327215 | — | ◇ UNVERIFIED |
| CGCarr-lowrey Glass | Baltimore | MD | Nonmetallic Mineral Product Manufacturing327213 | — | ◇ UNVERIFIED |
| CEChaney Enterprises Limited Partnership | Hyattsville | MD | Nonmetallic Mineral Product Manufacturing327320 | — | ◇ UNVERIFIED |
| CGClassic Granite & Marble, INC. | Jessup | MD | Nonmetallic Mineral Product Manufacturing327390 | — | ◇ UNVERIFIED |
| CWCommercial Window Solutions, INC. | Hyattsville | MD | Nonmetallic Mineral Product Manufacturing327215 | — | ◇ UNVERIFIED |
| CRConcierge Remodeling Services, INC. | Baltimore | MD | Nonmetallic Mineral Product Manufacturing327991 | — | ◇ UNVERIFIED |
| CWConcrete Works INC | Baltimore | MD | Nonmetallic Mineral Product Manufacturing327320 | — | ◇ UNVERIFIED |
| CFCountry Floral Supply INC | Baltimore | MD | Nonmetallic Mineral Product Manufacturing327112 | — | ◇ UNVERIFIED |
| CCCowgirl Clay Studio, L.l.c. | Walkersville | MD | Nonmetallic Mineral Product Manufacturing327110 | — | ◇ UNVERIFIED |
| CCCumberland Concrete Corporation | Lavale | MD | Nonmetallic Mineral Product Manufacturing327310 | — | ◇ UNVERIFIED |
| CWC. William Hetzer/beaver Creek West | Hagerstown | MD | Petroleum and Coal Products Manufacturing324121 | — | ◇ UNVERIFIED |
| DRDorsey Run Lp, Llc/annapolis Junction Plant | Jessup | MD | Nonmetallic Mineral Product Manufacturing327991 | — | ◇ UNVERIFIED |
| EMErnest Maier INC. | Ocean City | MD | Nonmetallic Mineral Product Manufacturing327331 | — | ◇ UNVERIFIED |
| FEFritz Enterprises | Sparrows Point | MD | Nonmetallic Mineral Product Manufacturing327992 | — | ◇ UNVERIFIED |
| GGGo Glass Joy, LLC | Salisbury | MD | Nonmetallic Mineral Product Manufacturing327211 | — | ◇ UNVERIFIED |
| GIGranix, INC. | Columbia | MD | Nonmetallic Mineral Product Manufacturing327991 | — | ◇ UNVERIFIED |