| OCOdum Concrete Products INC | Herrin | IL | — | ◇ UNVERIFIED |
| OCOgden Concrete Batch Plant G19 | Ogden | UT | — | ◇ UNVERIFIED |
| OROhio River Concrete CORP | Marion | KY | — | ◇ UNVERIFIED |
| OAOkeechobee Asphalt/concrete Plant, Cw Roberts Contracting INC. | Okeechobee | FL | — | ◇ UNVERIFIED |
| OOldcastle | Eugene | OR | — | ◇ UNVERIFIED |
| OOldcastle | Lebanon | PA | — | ◇ UNVERIFIED |
| OOldcastle | Keizer | OR | — | ◇ UNVERIFIED |
| OAOldcastle Adams Products - Ridgeway | Ridgeway | SC | — | ◇ UNVERIFIED |
| OAOldcastle Apg South INC | Rockwood | TN | — | ◇ UNVERIFIED |
| OAOldcastle Apg South, INC | Lehigh Acres | FL | — | ◇ UNVERIFIED |
| OAOldcastle Apg South, INC. | Auburndale | FL | — | ◇ UNVERIFIED |
| OAOldcastle Apg Texas INC (dba Custom-crete) | Frisco | TX | — | ◇ UNVERIFIED |
| OAOldcastle Apg West/dba Superlite Block | Needles | CA | — | ◇ UNVERIFIED |
| OAOldcastle Architectural West INC | Keller | TX | — | ◇ UNVERIFIED |
| OAOldcastle Architectural West INC | Balch Springs | TX | — | ◇ UNVERIFIED |
| OAOldcastle Architectural West INC | Houston | TX | — | ◇ UNVERIFIED |
| OCOldcastle Coastal | Tampa | FL | — | ◇ UNVERIFIED |
| OCOldcastle Coastal INC | Fort Myers | FL | — | ◇ UNVERIFIED |
| OCOldcastle Coastal, INC. | Jacksonville | FL | — | ◇ UNVERIFIED |
| OCOld Castle Dba United - Two Feathers Pit | Montrose | CO | — | ◇ UNVERIFIED |
| OEOldcastle Enclosure Solutions | Tracy | CA | — | ◇ UNVERIFIED |
| OIOldcastle Infrastructure | Stockton | CA | — | ◇ UNVERIFIED |
| OIOldcastle Infrastructure | Romeoville | IL | — | ◇ UNVERIFIED |
| OIOldcastle Infrastructure | Nampa | ID | — | ◇ UNVERIFIED |
| OIOldcastle Infrastructure | Acworth | GA | — | ◇ UNVERIFIED |
| OIOldcastle Infrastructure | Midway | FL | — | ◇ UNVERIFIED |
| OIOldcastle Infrastructure INC | Chowchilla | CA | — | ◇ UNVERIFIED |
 Oldcastle Infrastructure, INC - Fontana | Fontana | CA | — | ◇ UNVERIFIED |
| Oldcastle Infrastructure, INC. - Phoenix Oes | Phoenix | AZ | — | ◇ UNVERIFIED |
| OIOldcastle Infrastructure - Platteville | Loveland Area | CO | — | ◇ UNVERIFIED |
| OMOldcastle Materials, INC. | Tampa | FL | — | ◇ UNVERIFIED |
| OMOldcastle Materials, INC. | Gainesville | FL | — | ◇ UNVERIFIED |
| ONOldcastle Nampa Madison | Nampa | ID | — | ◇ UNVERIFIED |
| OPOldcastle Precast | Perris | CA | — | ◇ UNVERIFIED |
| OPOldcastle Precast | Fontana | CA | — | ◇ UNVERIFIED |
| OPOldcastle Precast INC | Tualatin | OR | — | ◇ UNVERIFIED |
| OPOldcastle Precast INC | Greensboro | NC | — | ◇ UNVERIFIED |
| OPOldcastle Precast INC | Bartow | FL | — | ◇ UNVERIFIED |
| OPOldcastle Precast INC | Elk River | MN | — | ◇ UNVERIFIED |
| OPOldcastle Precast INC | Clackamas | OR | — | ◇ UNVERIFIED |
| OPOldcastle Precast INC | Stone Mountain | GA | — | ◇ UNVERIFIED |
| OPOldcastle Precast, INC. | Ontario | CA | — | ◇ UNVERIFIED |
| OSOldcastle Savannah | Guyton | GA | — | ◇ UNVERIFIED |
| OSOldcastle Sw Group - 1771 Shields Dr | Steamboat Springs | CO | — | ◇ UNVERIFIED |
| OSOldcastle Sw Group - Anderson Rmc | Delta | CO | — | ◇ UNVERIFIED |
| OSOldcastle Sw Group Dba Telluride Gravel | Telluride | CO | — | ◇ UNVERIFIED |
| OSOldcastle Sw Group, INC. Dba B&b Excavat | Eagle | CO | — | ◇ UNVERIFIED |
| OSOldcastle Sw Group, INC. Dba B&b Excavat | 0.5 Miles West of Edwardsq | CO | — | ◇ UNVERIFIED |
| OSOldcastle Sw Group INC Dba Four Corners | Pagosa Springs | CO | — | ◇ UNVERIFIED |
| OSOldcastle Sw Group INC. Dba Four Corners | Cortez | CO | — | ◇ UNVERIFIED |
| OSOldcastle Sw Group INC. Dba Four Corners | Durango 4.1 Mi. N of | CO | — | ◇ UNVERIFIED |
| OSOldcastle Sw Group INC Dba United CO of | Paonia | CO | — | ◇ UNVERIFIED |
| OSOldcastle Sw Group - Minturn Concrete | Minturn | CO | — | ◇ UNVERIFIED |
| OSOldcastle Sw Group- Port Concrete Plant | Gunnison | CO | — | ◇ UNVERIFIED |
| OSOldcastle Sw Group - Rifle Rmc Plant | Rifle | CO | — | ◇ UNVERIFIED |
| OSOldcastle Sw Grp - Gunnison Redi-mix Pit | Gunnison Area | CO | — | ◇ UNVERIFIED |
| OUOldcastle United Comp of Mesa County | Rifle | CO | — | ◇ UNVERIFIED |
| OWOldcastle Westile, INC. | Littleton | CO | — | ◇ UNVERIFIED |
| OMOld Metro Parkway Concrete Plant | Fort Myers | FL | — | ◇ UNVERIFIED |
| OSOltman & Sons INC | Henry | IL | — | ◇ UNVERIFIED |
| OMOlympic Marble | Buena Park | CA | — | ◇ UNVERIFIED |
| OWOmaha Wilbert Vault, INC. | Omaha | NE | — | ◇ UNVERIFIED |
| OPOmega Products International, INC. | Commerce City | CO | — | ◇ UNVERIFIED |
| OPOmni Products, INC. | Lincolnton | NC | — | ◇ UNVERIFIED |
| OPOneonta Plant | Oneonta | AL | — | ◇ UNVERIFIED |
| OROrangeburg Redi-mix Concrete | Orangeburg | SC | — | ◇ UNVERIFIED |
| OROrangeburg Redi-mix Concrete INC Bamberg Plant | Bamberg | SC | — | ◇ UNVERIFIED |
| OROrangeburg Redi-mix Concrete INC Harleyville | Harleyville | SC | — | ◇ UNVERIFIED |
| OBOrco Blended Products INC | Highland | CA | — | ◇ UNVERIFIED |
| OBOrco Block CO | Oceanside | CA | — | ◇ UNVERIFIED |
| OOOregon On-site Concrete INC | Sherwood | OR | — | ◇ UNVERIFIED |
| OMOremus Material LLC | Chicago | IL | — | ◇ UNVERIFIED |
| OROrgain Ready Mix Concrete Co., INC. | Murfreesboro | TN | — | ◇ UNVERIFIED |
| OROrgain Ready Mix Concrete Company, INC. | Pleasant View | TN | — | ◇ UNVERIFIED |
| OROriginal Rock Replicas of Arizona, INC. | Tempe | AZ | — | ◇ UNVERIFIED |
| OAOrlando Airport | Orlando | FL | — | ◇ UNVERIFIED |
| OCOrnamental Columns and Statues, INC. | Fort Myers | FL | — | ◇ UNVERIFIED |
| OSOrnamental Stone INC | Allyn | WA | — | ◇ UNVERIFIED |
| OCOsage County Industries | Linn | MO | — | ◇ UNVERIFIED |
| OCOsage County Industries Inc-linn | Linn | MO | — | ◇ UNVERIFIED |
| OCOsborne Concrete & Stone CO (0243030583) | Grand River | OH | — | ◇ UNVERIFIED |
| OIOsborne INC | Mentor | OH | — | ◇ UNVERIFIED |
| OROscar Renda Contracting, INC. | Houston | TX | — | ◇ UNVERIFIED |
| OCOsceola Concrete LLC | Osceola | MO | — | ◇ UNVERIFIED |
| O0Otfl 001 Eastside Ready Mix379 | San Antonio | TX | — | ◇ UNVERIFIED |
| OIOutback Inc.-oneals Yard | O'neals | CA | — | ◇ UNVERIFIED |
| OMOutback Materials | Mariposa | CA | — | ◇ UNVERIFIED |
| OMOutback Materials | Fresno | CA | — | ◇ UNVERIFIED |
| OMOutback Materials, INC. | O'neals | CA | — | ◇ UNVERIFIED |
| OROverland Ready Mixed Concrete | Strang | NE | — | ◇ UNVERIFIED |
| OROverland Ready Mixed Super 8 | Fullerton | NE | — | ◇ UNVERIFIED |
| OSOverland Sand & Gravel Mowitz | Central City | NE | — | ◇ UNVERIFIED |
| OSOverton Sand & Gravel CO | Lexington | NE | — | ◇ UNVERIFIED |
| OSOverton Sand & Gravel CO. | Riverdale | NE | — | ◇ UNVERIFIED |
| OSOverton Sand & Gravel Company | Overton | NE | — | ◇ UNVERIFIED |
| OAOwens and Son's Vault Company | Union Springs | AL | — | ◇ UNVERIFIED |
| OCOwensboro Concrete CO | Owensboro | KY | — | ◇ UNVERIFIED |
| OBOwens Brothers Concrete CO | Arvada | CO | — | ◇ UNVERIFIED |
| ODOxford Division of B and B Concrete Company INC | Oxford | MS | — | ◇ UNVERIFIED |
| OSOxford Sand Company Inc, Pontotoc Plant | Pontotoc | MS | — | ◇ UNVERIFIED |
