| MMMartin Marietta Titan Ready Mix | Littleton | CO | — | ◇ UNVERIFIED |
| MMaschmeyer-apollo(blk/rm) | Apollo Beach | FL | — | ◇ UNVERIFIED |
| MPMaschmeyer-cement Products | Lakeland | FL | — | ◇ UNVERIFIED |
| MCMaschmeyer Concrete Company INC | Lake Park | FL | — | ◇ UNVERIFIED |
| MCMaschmeyer Concrete Company of Florida | West Palm Beach | FL | — | ◇ UNVERIFIED |
| MCMaschmeyer Concrete Company of Florida | Deltona | FL | — | ◇ UNVERIFIED |
| MCMaschmeyer Concrete CO of Florida INC | Orlando | FL | — | ◇ UNVERIFIED |
| MCMaschmeyer Concrete CO of Florida INC | Davenport | FL | — | ◇ UNVERIFIED |
| MCMaschmeyer Concrete CO of Florida INC | Casselberry | FL | — | ◇ UNVERIFIED |
| MCMaschmeyer Concrete CO of Florida INC | Debary | FL | — | ◇ UNVERIFIED |
| MCMaschmeyer Concrete - Fort Pierce Plant | Fort Pierce | FL | — | ◇ UNVERIFIED |
| MCMaschmeyer Concrete - Stuart Plant | Stuart | FL | — | ◇ UNVERIFIED |
| MCMaschmeyer Concrete Taft Facility | Orlando | FL | — | ◇ UNVERIFIED |
| MRMaschmeyer-lakeland Rm | Lakeland | FL | — | ◇ UNVERIFIED |
| MRMaschmeyer-loughman Rm | Davenport | FL | — | ◇ UNVERIFIED |
| MRMaschmeyer-melbourne Rm | Melbourne | FL | — | ◇ UNVERIFIED |
| MRMaschmeyer-onsite-universal Rm | Orlando | FL | — | ◇ UNVERIFIED |
| MRMaschmeyer-sligh Rm | Tampa | FL | — | ◇ UNVERIFIED |
| MCMaschmeyer-st. Cloud Rm | Saint Cloud | FL | — | ◇ UNVERIFIED |
| MMaschmeyer-vero(blk-rm) | Vero Beach | FL | — | ◇ UNVERIFIED |
| MZMaschmeyer - Zephyrhills | Zephyrhills | FL | — | ◇ UNVERIFIED |
| MSMccabe Sand & Gravel | Taunton | MA | — | ◇ UNVERIFIED |
| MCMccoig Concrete-springwells | Detroit | MI | — | ◇ UNVERIFIED |
| MCMcminnville Concrete | Mcminnville | OR | — | ◇ UNVERIFIED |
| MCMechanicsville Concrete Llc-airport Plant (oakleys Lane) | Henrico | VA | — | ◇ UNVERIFIED |
| MCMechanicsville Concrete LLC - Chesterfield Plant | Midlothian | VA | — | ◇ UNVERIFIED |
| MPMelissa Plant | Melissa | TX | — | ◇ UNVERIFIED |
| MCMerit Concrete | Laurel | MD | — | ◇ UNVERIFIED |
| MMetalico-evans | Atlanta | GA | — | ◇ UNVERIFIED |
| MCMetro Concrete | Ocean Springs | MS | — | ◇ UNVERIFIED |
| MMMetro Materials INC Cordova | Cordova | TN | — | ◇ UNVERIFIED |
| MMMetro Mix LLC | Denver | CO | — | ◇ UNVERIFIED |
| MRMetromont:clemson Ready-mix Plant | Seneca | SC | — | ◇ UNVERIFIED |
| MMMetromont Materials CORP Holly Hill | Holly Hill | SC | — | ◇ UNVERIFIED |
| MMMetromont Materials Corporation - Hamlet Plant | Hamlet | NC | — | ◇ UNVERIFIED |
| MPMetromont Paris Mountain | Greenville | SC | — | ◇ UNVERIFIED |
| MMMeyer Material CO Kenosha 20 | Kenosha | WI | — | ◇ UNVERIFIED |
| MMMeyer Material CO Kenosha 40 | Kenosha | WI | — | ◇ UNVERIFIED |
| MMMeyer Material CO Middlebury Ready Mix Plant | Middlebury | IN | — | ◇ UNVERIFIED |
| MMMeyer Material Company | Milwaukee | WI | — | ◇ UNVERIFIED |
| MMMeyer Material CO Warsaw Ready Mix Plant | Warsaw | IN | — | ◇ UNVERIFIED |
| MCMid Continent Concrete CO / 431 W 23rd St Tulsa Facility | Tulsa | OK | — | ◇ UNVERIFIED |
| MPMidlothian Plant | Midlothian | TX | — | ◇ UNVERIFIED |
| MBMidtown Batch Plant | Oklahoma City | OK | — | ◇ UNVERIFIED |
| MPMidwest Precast Concrete Enterprises INC | Mount Pleasant | IA | — | ◇ UNVERIFIED |
| MPMidwest Premix - Jefferson City | Jefferson City | MO | — | ◇ UNVERIFIED |
| MMMiller Material CO | Kansas City | MO | — | ◇ UNVERIFIED |
| MPMiramar Plant 33 | San Diego | CA | — | ◇ UNVERIFIED |
| MCMm Cleburne Ready Mix | Cleburne | TX | — | ◇ UNVERIFIED |
 Mmc Materials | Batesville | MS | — | ◇ UNVERIFIED |
