| NYSE | NYT | 108 |
| NYSE | O | 67 |
| NASDAQ | OABI | 25 |
| NASDAQ | OAKU | 1 |
| NASDAQ | OAS | 53 |
| NASDAQ | OB | 10 |
| NASDAQ | OBCI | 13 |
| NYSE | OBDC | 4 |
| NYSE | OBDE | 2 |
| NASDAQ | OBIO | 13 |
| NASDAQ | OBNK | 19 |
| NASDAQ | OBT | 20 |
| NYSE | OC | 106 |
| NYSE | OCA | 4 |
| NASDAQ | OCAX | 1 |
| NASDAQ | OCC | 19 |
| NASDAQ | OCCI | 55 |
| NASDAQ | OCDX | 10 |
| NASDAQ | OCFC | 87 |
| NASDAQ | OCGN | 56 |
| NYSE | OCN | 61 |
| NASDAQ | OCSL | 183 |
| NASDAQ | OCUL | 77 |
| NASDAQ | OCUP | 9 |
| NASDAQ | OCX | 18 |
| NYSE | ODC | 61 |
| NASDAQ | ODFL | 51 |
| NASDAQ | ODP | 77 |
| NYSE | OEC | 30 |
| NASDAQ | OEG | 14 |
| NASDAQ | OESX | 106 |
| NYSE | OFC | 105 |
| NASDAQ | OFED | 6 |
| NYSE | OFG | 96 |
| NASDAQ | OFIX | 70 |
| NASDAQ | OFLX | 24 |
| NASDAQ | OFS | 11 |
| NYSE | OGE | 63 |
| NYSE | OGN | 6 |
| NYSE | OGS | 20 |
| NYSE | OHI | 101 |
| NYSE | OI | 38 |
| NYSE | OIA | 5 |
| NYSE | OII | 54 |
| NYSE | OIS | 35 |
| NYSE | OKE | 31 |
| NYSE | OKLO | 9 |
| NASDAQ | OKTA | 315 |
| NASDAQ | OKUR | 8 |
| NASDAQ | OLB | 13 |
