| Entity Name | Type | License # | City | Status | Action |
|---|---|---|---|---|---|
| OFF DUTY SERVICES INC | Business | 122001437 | CHICAGO | ACTIVE | Verify |
| OFFICIAL SECURITY SYSTEMS | Business | 117000333 | CHICAGO | NOT RENEWED | Verify |
| OFFICIAL SECURITY SYSTEMS INC | Business | 127000033 | CHICAGO | NOT RENEWED | Verify |
| OFFICIAL SECURITY SYSTEMS INC | Business | 122000205 | CHICAGO | NOT RENEWED | Verify |
| OGDEN ALLIED EASTERN | Business | 122000608 | CHICAGO | NOT RENEWED | Verify |
| OGDEN ALLIED SECURITY SERVICES INC | Business | 122000303 | CHICAGO | NOT RENEWED | Verify |
| OGDEN ALLIED SECURITY SERVICES INC | Business | 122000303 | CHICAGO | NOT RENEWED | Verify |
| OGDEN ALLIED SECURITY SERVICES INC | Business | 117000373 | CHICAGO | INOPERATIVE | Verify |
| OGDEN ALLIED SECURITY SERVICES INC | Business | 127000709 | CHICAGO | NOT RENEWED | Verify |
| OGDEN FAIRMOUNT SECURITY | Business | 120100007 | COLLINSVILLE | NOT RENEWED | Verify |
| OGDEN SECURITY INC | Business | 201000235 | CICERO | ACTIVE | Verify |
| OGVALE PROPERTIES | Business | 120500090 | CHICAGO | NOT RENEWED | Verify |
| OHLSON INVESTIGATION | Business | 201000218 | ROSELLE | ACTIVE | Verify |
| OHLSON INVESTIGATION | Business | 127000039 | BLOOMINGDALE | NOT RENEWED | Verify |
| OHLSON INVESTIGATION | Business | 117000184 | ROSELLE | NOT RENEWED | Verify |
| OHLSON INVESTIGATION | Business | 102000055 | ROSELLE | ACTIVE | Verify |
| OHLSON INVESTIGATION | Business | 118000137 | WAUKEGAN | NOT RENEWED | Verify |
| OHLSON INVESTIGATION & SECURITY SERVICE INC | Business | 122000131 | ROSELLE | NOT RENEWED | Verify |
| OHLSON INVESTIGATION & SECURITY SERVICE INC | Business | 122000131 | ROSELLE | NOT RENEWED | Verify |
| OHLSON INVESTIGATION & SECURITY SERVICE INC | Business | 123000137 | WAUKEGAN | CLOSED | Verify |
| OK ELECTRIC COMPANY INC | Business | 127000427 | NAPERVILLE | NOT RENEWED | Verify |
| OKAW VALLEY ENTERTAINMENT INC | Business | 120100034 | SHELBYVILLE | NOT RENEWED | Verify |
| OLD CHICAGO INVESTIGATIONS | Business | 117001389 | POSEN | NOT RENEWED | Verify |
| OLD DOMINION SECURITY CO INC | Business | 122001342 | CHICAGO | NOT RENEWED | Verify |
| OLD KENT BANK CHICAGO | Business | 120500041 | CHICAGO | CLOSED | Verify |
| OLIPHANT LOCK & SAFE | Business | 192000230 | LOVES PARK | ACTIVE | Verify |
| OLIVE HARVEY COLLEGE | Business | 102000061 | CHICAGO | ACTIVE | Verify |
| OLIVE-HARVEY COLLEGE | Business | 102000267 | CHICAGO | ACTIVE | Verify |
| OLYMPIA INVESTIGATIONS | Business | 201000150 | OLYMPIA FIELDS | ACTIVE | Verify |
| OLYMPIAN SECURITY GROUP PLLC | Business | 122001703 | FRANKFORT | ACTIVE | Verify |
| OMEGA GLOBAL SECURITY SERVICES INC | Business | 122001365 | CHICAGO | ACTIVE | Verify |
| OMEGA GROUP INVESTIGATIONS LLC | Business | 117001555 | CHICAGO | NOT RENEWED | Verify |
| OMEGA INVESTIGATION | Business | 117000552 | TINLEY PARK | NOT RENEWED | Verify |
| OMEGA PRO SYSTEMS INC | Business | 127001597 | BENSENVILLE | ACTIVE | Verify |
| OMEGA SECURITY SYSTEMS INC | Business | 127000784 | BLOOMINGDALE | NOT RENEWED | Verify |
| OMEGA SECURITY SYSTEMS INC | Business | 128000036 | BLOOMINGDALE | INACTIVE | Verify |
| OMNI I ELECTRONICS INC | Business | 128000101 | MOUNT VERNON | NOT RENEWED | Verify |
| OMNI I ELECTRONICS INC | Business | 127000079 | CHICAGO | ACTIVE | Verify |
| OMNI LOCK SERVICE | Business | 192000167 | ALGONQUIN | CHANGE OF OWNERSHIP | Verify |
| OMNI LOCKS | Business | 192000286 | ALGONQUIN | NOT RENEWED | Verify |
| OMNI SECURITY GROUP INC | Business | 122000283 | CHICAGO | NOT RENEWED | Verify |
| OMNI SECURITY GROUP INC | Business | 127000306 | HARWOOD HEIGHTS | NOT RENEWED | Verify |
| OMNI SECURITY GROUP INC | Business | 117000219 | HARWOOD HEIGHTS | NOT RENEWED | Verify |
| OMNI SECURITY ROCHESTER INC | Business | 127001388 | DES PLAINES | NOT RENEWED | Verify |
| ON CALL LOCKSMITH INC | Business | 192000343 | BOLINGBROOK | ACTIVE | Verify |
| ON GUARD INC | Business | 127000947 | SCHAUMBURG | NOT RENEWED | Verify |
| ON GUARD INC | Business | 127000836 | TINLEY PARK | ACTIVE | Verify |
| ON GUARD SECURITY/SENTINEL CORPS PATROL | Business | 123000199 | GENEVA | NOT RENEWED | Verify |
| ON GUARD SECURITY/SENTINEL CORPS PATROL | Business | 123000177 | CHICAGO | NOT RENEWED | Verify |
| ON GUARD SECURITY/SENTINEL CORPS PATROL | Business | 123000186 | CHICAGO | NOT RENEWED | Verify |