| OCO'hare Concrete Plant | Chicago | IL | — | ◇ UNVERIFIED |
| OSOil Spill (blacklidge Emulsions,, Inc.) | Gulfport | MS | — | ◇ UNVERIFIED |
| OAOlathe Aggregate Facilities (stormwater) | Olathe | KS | — | ◇ UNVERIFIED |
| OOldcastle | Morgan Hill | CA | — | ◇ UNVERIFIED |
| OOldcastle | Lockport | IL | — | ◇ UNVERIFIED |
| OOldcastle | Kenosha | WI | — | ◇ UNVERIFIED |
| OOldcastle | Elgin | IL | — | ◇ UNVERIFIED |
| OAOldcastle Adams Products | Clarksville | TN | — | ◇ UNVERIFIED |
| OAOldcastle Apg Company, Great Lakes | Cincinnati | OH | — | ◇ UNVERIFIED |
| OAOldcastle Apg Mid-atlantic | Chesapeake | VA | — | ◇ UNVERIFIED |
| OAOldcastle Apg Mid-atlantic Crofton, Md | Odenton | MD | — | ◇ UNVERIFIED |
| OAOldcastle Apg Mid-atlantic Richmond, Va | Richmond | VA | — | ◇ UNVERIFIED |
| OAOldcastle Apg Natl I/emigsville | Emigsville | PA | — | ◇ UNVERIFIED |
| OAOldcastle Apg New England | Victor | NY | — | ◇ UNVERIFIED |
| OAOldcastle Apg New England | Cranston | RI | — | ◇ UNVERIFIED |
| OAOldcastle Apg Northeast, INC. | Manheim | PA | — | ◇ UNVERIFIED |
| OAOldcastle Apg Northeast, INC. | West Lebanon | NH | — | ◇ UNVERIFIED |
| OAOldcastle Architectural West INC | Dallas | TX | — | ◇ UNVERIFIED |
| OAOldcastle Architectural West INC | Rosenberg | TX | — | ◇ UNVERIFIED |
| OAOldcastle Architectural West INC | Austin | TX | — | ◇ UNVERIFIED |
| OCOldcastle - Crested Butte Rmc Plant | Crested Butte Area | CO | — | ◇ UNVERIFIED |
| OCOld Castle Dba United - Two Feathers Pit | Montrose | CO | — | ◇ UNVERIFIED |
| OIOldcastle Infrastructure | Acworth | GA | — | ◇ UNVERIFIED |
| OIOldcastle Infrastructure | Platteville | CO | — | ◇ UNVERIFIED |
 Oldcastle Infrastructure INC. - Courtland | Courtland | MN | — | ◇ UNVERIFIED |
| OMOldcastle Matt Stone Holdings Incorporated | Cowpens | SC | — | ◇ UNVERIFIED |
| OPOldcastle Precast | Kalamazoo | MI | — | ◇ UNVERIFIED |
| OPOldcastle Precast | Houston | TX | — | ◇ UNVERIFIED |
| OPOldcastle Precast | Easton | PA | — | ◇ UNVERIFIED |
| OPOldcastle Precast | Mansfield | TX | — | ◇ UNVERIFIED |
| OPOldcastle Precast | Lakeside | CA | — | ◇ UNVERIFIED |
| OPOldcastle Precast Brookshire Plant | Brookshire | TX | — | ◇ UNVERIFIED |
| OPOldcastle Precast INC | Chandler | AZ | — | ◇ UNVERIFIED |
| OPOldcastle Precast INC | Manchester | NY | — | ◇ UNVERIFIED |
| OPOldcastle Precast INC | Morrisville | PA | — | ◇ UNVERIFIED |
| OPOldcastle Precast INC | Bartow | FL | — | ◇ UNVERIFIED |
| OPOldcastle Precast INC | Folsom | NJ | — | ◇ UNVERIFIED |
| OPOldcastle Precast INC | Medley | FL | — | ◇ UNVERIFIED |
| OPOldcastle Precast INC | Greensboro | NC | — | ◇ UNVERIFIED |
| OPOldcastle Precast INC. | Jacksonville | FL | — | ◇ UNVERIFIED |
| OPOldcastle Precast INC. | Edgewood | MD | — | ◇ UNVERIFIED |
| OPOldcastle Precast, INC. - Bellingham | Bellingham | WA | — | ◇ UNVERIFIED |
| OPOldcastle Precast, INC. - Jacksonvillesp | Jacksonville | FL | — | ◇ UNVERIFIED |
| OPOldcastle Precast, INC. - Tallahasseesp | Midway | FL | — | ◇ UNVERIFIED |
| OPOldcastle Precast San Antonio Plant | San Antonio | TX | — | ◇ UNVERIFIED |
| OROldcastle Retail, INC. | Jacksonville | FL | — | ◇ UNVERIFIED |
| OSOldcastle Sw Group - 1771 Shields Dr | Steamboat Springs | CO | — | ◇ UNVERIFIED |
| OSOldcastle Sw Group - Cugnini Pit | Durango | CO | — | ◇ UNVERIFIED |
| OSOldcastle Sw Group Dba B&b Excavating | Eagle | CO | — | ◇ UNVERIFIED |
| OSOldcastle Sw Group Dba Four Conrners | Durango 2.5 Mi Se of | CO | — | ◇ UNVERIFIED |
