| Entity Name | Type | License # | City | Status | Action |
|---|---|---|---|---|---|
| OEDIFICE ENGINEERING INC | Business | 184002190-0002 | CHAMPAIGN | NOT RENEWED | Verify |
| OFFENBERG-TIRITILLI LTD | Business | 184002160-0001 | CHICAGO | NOT RENEWED | Verify |
| OFFICE DFK, PLLC | Business | 184008281-0001 | CHICAGO | NOT RENEWED | Verify |
| OFFICE FOR URBAN EXPERIMENTS | Business | 184007107-0001 | CHICAGO | NOT RENEWED | Verify |
| OFFICE OF THINGS PLLC | Business | 184008544-0001 | CHICAGO | ACTIVE | Verify |
| OGDEN ENGINEERING AND CONSTRUCTION LLC | Business | 184009000-0002 | WESTMONT | NOT RENEWED | Verify |
| OISSE ARCHITECTS INC. | Business | 184005306-0001 | DEERFIELD | NOT RENEWED | Verify |
| OKA ENGINEERING PLLC | Business | 184008714-0002 | FAIRVIEW HEIGHTS | ACTIVE | Verify |
| OKAW VALLEY LAND SURVEYING | Business | 184002717-0008 | SULLIVAN | CANCELLED | Verify |
| OKAW VALLEY LAND SURVEYING LLC | Business | 184004388-0008 | SULLIVAN | NOT RENEWED | Verify |
| OKW ARCHITECTS INC | Business | 184000553-0001 | CHICAGO | CLOSED | Verify |
| OKW ARCHITECTS PLLC | Business | 184008313-0001 | CHICAGO | ACTIVE | Verify |
| OLEN ARCHITECTURE LLC | Business | 184005993-0001 | NAPERVILLE | ACTIVE | Verify |
| OLESON DESIGN STUDIO PLLC | Business | 184007238-0001 | ROUND LAKE | ACTIVE | Verify |
| OLIVET ENGINEERING GROUP, PC | Business | 184007587-0002 | KANKAKEE | NOT RENEWED | Verify |
| OLIVIERI BROTHERS INC | Business | 184000489-0001 | MOKENA | NOT RENEWED | Verify |
| OLLMANN ERNEST MARTIN ARCHITECTS | Business | 184004048-0004 | BELVIDERE | ACTIVE | Verify |
| OLRIKSEN BUNDA & MOELL INC | Business | 184000258-0005 | BLOOMINGDALE | NOT RENEWED | Verify |
| OLSEN & ASSOCIATES ARCHITECTS | Business | 184004260-0001 | CHAMPAIGN | NOT RENEWED | Verify |
| OLSEN VRANAS DESIGN LLC | Business | 184005276-0001 | CHICAGO | NOT RENEWED | Verify |
| OLSON ARCHITECTURAL | Business | 184008315-0001 | CHICAGO | ACTIVE | Verify |
| OLYMPIC ENGINEERING PC | Business | 184003589-0006 | ELK GROVE VILLAGE | ACTIVE | Verify |
| OMEGA & ASSOCIATES INC | Business | 184003562-0010 | LISLE | CANCELLED | Verify |
| ONLINE LAND SURVEYING PLLC | Business | 184004603-0008 | PARK RIDGE | ACTIVE | Verify |
| ONSITE ENGINEERING LLC | Business | 184004257-0002 | DECATUR | ACTIVE | Verify |
| ONYX ARCHITECTURE SERVICES INC | Business | 184003405-0004 | CHICAGO | ACTIVE | Verify |
| OOMO STUDIO LLC | Business | 184005813-0001 | RIVERSIDE | ACTIVE | Verify |
| OPERAM ARCHTECTURE PLLC | Business | 184009013-0001 | CHICAGO | NOT RENEWED | Verify |
| OPLIS ENGINEERS LLC | Business | 184006089-0002 | CHICAGO | NOT RENEWED | Verify |
| OPPERMANN ARCHITECTS LTD | Business | 184000730-0001 | NAPERVILLE | NOT RENEWED | Verify |
| OPPIDANUSA INC | Business | 184000461-0001 | CHICAGO | NOT RENEWED | Verify |
| OPTIMA INC | Business | 184002287-0001 | GLENCOE | NOT RENEWED | Verify |
| ORANGE ARCHITECTURE PC | Business | 184004574-0001 | CHICAGO | NOT RENEWED | Verify |
| ORBIS ARCHITECTS INC | Business | 184006248-0001 | LOCKPORT | NOT RENEWED | Verify |
| ORD BASIN GROUP LLC | Business | 184003822-0006 | CHICAGO | CANCELLED | Verify |
| ORD GREEN SPIRIT LLC | Business | 184005465-0015 | CHICAGO | NOT RENEWED | Verify |
| ORD RR GROUP LLC | Business | 184003825-0006 | CHICAGO | CANCELLED | Verify |
| ORDERS ARCHITECTURE + DESIGN PLLC | Business | 184009253-0001 | CHICAGO | ACTIVE | Verify |
| ORG INC | Business | 184009089-0001 | CHICAGO | ACTIVE | Verify |
| ORION ENGINEERS PLLC | Business | 184007169-0006 | CHICAGO | ACTIVE | Verify |
| ORLYNBOCK DESIGN LLC | Business | 184007912-0001 | CHICAGO | NOT RENEWED | Verify |
| ORREN PICKELL DESIGN GROUP INC | Business | 184001975-0001 | WILMETTE | ACTIVE | Verify |
| OSA ENGINEERS INC | Business | 184002864-0002 | SKOKIE | NOT RENEWED | Verify |
| OSBORNE ENGINEERING INC | Business | 184007265-0002 | WILMETTE | ACTIVE | Verify |
| OSEH INC | Business | 184007766-0002 | WHEATON | ACTIVE | Verify |
| OSF DESIGN GROUP INC | Business | 184004145-0001 | PEORIA | NOT RENEWED | Verify |
| OSTERHAUS MCCARTHY LLC | Business | 184004035-0001 | CHICAGO | NOT RENEWED | Verify |
| OTA INC | Business | 184005738-0001 | EVANSTON | ACTIVE | Verify |
| OVERLY ASSOCIATES INC | Business | 184002026-0006 | WASHINGTON | NOT RENEWED | Verify |
| OWEN CIVIL PLLC | Business | 184008844-0010 | HARRISBURG | ACTIVE | Verify |