| O2A | Blue Cross of California | |
| O2E | Blue Cross of California | |
| O2N | Highmark BCBS of Pennsylvania | |
| O2T | Blue Cross Blue Shield of Minnesota | |
| O3T | Regence Blue Cross Blue Shield of Oregon | |
| O3V | Premera Blue Cross | |
| OAA | Blue Cross Blue Shield of Massachusetts | |
| OAB | Blue Cross Blue Shield of Massachusetts | |
| OAC | Anthem BCBS of Ohio | |
| OAD | BCBS of Western New York | |
| OAE | Anthem BCBS of Ohio | |
| OAF | Anthem BCBS of Virginia | |
| OAG | Anthem BCBS of Colorado | |
| OAH | Empire Blue Cross Blue Shield | |
| OAI | Blue Shield of California | |
| OAJ | Unassigned | |
| OAK | Independence Blue Cross | |
| OAL | Blue Shield of California | |
| OAM | Highmark BCBS of Pennsylvania | |
| OAN | Unassigned | |
| OAO | Unassigned | |
| OAP | Anthem BCBS of Kentucky | |
| OAQ | CareFirst BCBS | |
| OAR | CareFirst BCBS | |
| OAS | Anthem BCBS of Ohio | |
| OAT | Blue Cross Blue Shield of Nebraska | |
| OAU | Blue Cross Blue Shield of Michigan | |
| OAV | Unassigned | |
| OAW | Unassigned | |
| OAX | CareFirst BCBS | |
| OAY | CareFirst BCBS | |
| OAZ | Blue Cross Blue Shield of Massachusetts | |
| OBA | Blue Cross of California | |
| OBB | Highmark BCBS | |
| OBC | Blue Cross Blue Shield of Massachusetts | |
| OBD | Blue Cross Blue Shield of South Carolina | |
| OBE | Blue Cross Blue Shield of Michigan | |
| OBF | Highmark BCBS of Pennsylvania | |
| OBG | BCBS of Tennessee | |
| OBH | CareFirst BCBS | |
| OBI | Blue Cross Blue Shield of Minnesota | |
| OBJ | Premera Blue Cross | |
| OBK | Unassigned | |
| OBL | CareFirst BCBS | |
| OBM | CareFirst BCBS | |
| OBN | Blue Cross Blue Shield of Massachusetts | |
| OBO | Highmark BCBS of Pennsylvania | |
| OBP | Blue Shield of California | |
| OBQ | Blue Cross of California | |
| OBR | Wellmark BCBS | |
| OBS | Blue Cross of Idaho | |
| OBT | Blue Cross Blue Shield of Arizona | |
| OBU | Blue Cross Blue Shield of Alabama | |
| OBV | Blue Cross of California | |
| OBW | Independence Blue Cross | |
| OBX | Blue Cross of California | |
| OBY | CareFirst BCBS | |
| OBZ | Blue Shield of California | |
| OCA | Blue Cross of California | |
| OCB | Anthem BCBS of Virginia | |
| OCC | Blue Cross of California | |
| OCD | Blue Shield of California | |
| OCE | Unassigned | |
| OCF | Anthem BCBS of Virginia | |
| OCG | Wellmark BCBS | |
| OCH | BCBS of Western New York | |
| OCI | Anthem BCBS of Wisconsin | |
| OCJ | Blue Shield of California | |
| OCK | Blue Cross Blue Shield of South Carolina | |
| OCL | CareFirst BCBS | |
| OCM | Wellmark BCBS | |
| OCN | Regence Blue Cross Blue Shield of Oregon | |
| OCO | Blue Shield of California | |
| OCP | Anthem BCBS of Ohio | |
| OCQ | Independence Blue Cross | |
| OCR | Independence Blue Cross | |
| OCS | BCBS of Florida | |
| OCT | Blue Cross of Idaho | |
| OCU | Anthem BCBS of Ohio | |
| OCV | CareFirst BCBS | |
| OCW | Blue Cross of California | |
| OCX | CareFirst BCBS | |
| OCY | CareFirst BCBS | |
| OCZ | Independence Blue Cross | |
| ODA | CareFirst BCBS | |
| ODB | Anthem BCBS of Ohio | |
| ODC | Wellmark BCBS | |
| ODD | Blue Cross Blue Shield of Nebraska | |
| ODE | Blue Cross of Idaho | |
| ODF | Blue Cross Blue Shield of Massachusetts | |
| ODG | Unassigned | |
| ODH | Blue Shield of California | |
| ODI | BCBS of Western New York | |
| ODJ | BCBS of Tennessee | |
| ODK | CareFirst BCBS | |
| ODL | BCBS of Tennessee | |
| ODM | Blue Cross Blue Shield of Arizona | |
| ODN | BCBS of Tennessee | |
| ODO | CareFirst BCBS | |
| ODP | Unassigned |
| ODQ | Highmark BCBS of Pennsylvania | |
| ODR | CareFirst BCBS | |
| ODS | BCBS of Western New York | |
| ODT | Blue Cross Blue Shield of Massachusetts | |
| ODU | Empire Blue Cross Blue Shield | |
| ODV | Wellmark BCBS | |
| ODW | Blue Cross Blue Shield of Michigan | |
| ODX | Blue Cross Blue Shield of Alabama | |
| ODY | Blue Cross Blue Shield of Michigan | |
| ODZ | Blue Cross Blue Shield of Michigan | |
| OEA | Anthem BCBS of Virginia | |
| OEB | Anthem BCBS of Virginia | |
| OEC | Excellus BCBS | |
| OED | Anthem BCBS of Virginia | |
| OEE | BCBS of Florida | |
| OEF | CareFirst BCBS | |
| OEG | Blue Cross Blue Shield of Kansas City | |
| OEH | Blue Cross of California | |
| OEI | Blue Cross Blue Shield of Nebraska | |
| OEJ | Blue Shield of California | |
| OEK | Blue Cross Blue Shield of Michigan | |
| OEL | CareFirst BCBS | |
| OEM | Anthem BCBS of Virginia | |
| OEN | Blue Cross Blue Shield of Alabama | |
| OEO | Blue Shield of California | |
| OEP | Capital BlueCross | |
| OEQ | Blue Cross Blue Shield of Michigan | |
| OER | Regence Blue Cross Blue Shield of Oregon | |
| OES | Blue Cross of California | |
| OET | CareFirst BCBS | |
| OEU | Highmark BCBS of Pennsylvania | |
| OEV | Highmark BCBS of Pennsylvania | |
| OEW | Blue Cross Blue Shield of North Dakota | |
| OEX | Blue Cross of California | |
| OEY | Blue Cross Blue Shield of Michigan | |
| OEZ | Blue Cross Blue Shield of South Carolina | |
| OFA | Anthem BCBS of Ohio | |
| OFB | Capital BlueCross | |
| OFC | Blue Cross Blue Shield of Michigan | |
| OFD | Highmark BCBS of Pennsylvania | |
| OFE | Unassigned | |
| OFF | BCBS of Western New York | |
| OFG | Blue Cross Blue Shield of Rhode Island | |
| OFH | Anthem BCBS of Ohio | |
| OFI | CareFirst BCBS | |
| OFJ | Blue Cross Blue Shield of Michigan | |
| OFK | Unassigned | |
| OFL | CareFirst BCBS | |
| OFM | CareFirst BCBS | |
| OFN | BCBS of Tennessee | |
| OFO | Blue Cross of California | |
| OFP | Blue Cross of California | |
| OFQ | Blue Cross Blue Shield of Michigan | |
| OFR | Anthem BCBS of Virginia | |
| OFS | BCBS of Western New York | |
| OFT | Blue Shield of California | |
| OFU | Blue Cross Blue Shield of Michigan | |
| OFV | Blue Cross Blue Shield of Michigan | |
| OFW | Blue Cross Blue Shield of Michigan | |
| OFX | Anthem BCBS of Missouri | |
| OFY | Blue Shield of California | |
| OFZ | Blue Cross Blue Shield of Michigan | |
| OGA | Unassigned | |
| OGB | Independence Blue Cross | |
| OGC | Wellmark BCBS | |
| OGD | Anthem BCBS of Ohio | |
| OGE | Blue Cross Blue Shield of Oklahoma | |
| OGF | Blue Cross Blue Shield of Michigan | |
| OGG | CareFirst BCBS | |
| OGH | Blue Cross Blue Shield of Georgia | |
| OGI | Blue Cross Blue Shield of Michigan | |
| OGJ | Blue Cross Blue Shield of Michigan | |
| OGK | Blue Cross Blue Shield of Michigan | |
| OGL | Wellmark BCBS | |
| OGM | Premera Blue Cross | |
| OGN | Anthem BCBS of Ohio | |
| OGO | Blue Cross Blue Shield of Michigan | |
| OGP | CareFirst BCBS | |
| OGQ | CareFirst BCBS | |
| OGR | Wellmark BCBS | |
| OGS | Blue Cross Blue Shield of Louisiana | |
| OGT | BCBS of Western New York | |
| OGU | Highmark BCBS of Pennsylvania | |
| OGV | CareFirst BCBS | |
| OGW | CareFirst BCBS | |
| OGX | CareFirst BCBS | |
| OGY | Premera Blue Cross | |
| OGZ | CareFirst BCBS | |
| OHA | Blue Cross Blue Shield of South Carolina | |
| OHB | Anthem BCBS of Ohio | |
| OHC | Blue Cross Blue Shield of Michigan | |
| OHD | Blue Cross Blue Shield of Texas | |
| OHE | Blue Cross Blue Shield of Rhode Island | |
| OHF | Anthem BCBS of Virginia | |
| OHG | Anthem BCBS of Virginia | |
| OHH | Anthem BCBS of Ohio | |
| OHI | Blue Cross Blue Shield of South Carolina | |
| OHJ | Anthem BCBS of Kentucky | |
| OHK | Wellmark BCBS | |
| OHL | Highmark BCBS of Pennsylvania |
| OHM | Blue Shield of Northeastern New York | |
| OHN | Wellmark BCBS | |
| OHO | Anthem BCBS of Ohio | |
| OHP | Anthem BCBS of Ohio | |
| OHQ | Unassigned | |
| OHR | Anthem BCBS of Colorado | |
| OHS | Anthem BCBS of Ohio | |
| OHT | Anthem BCBS of Ohio | |
| OHU | Wellmark BCBS | |
| OHV | Blue Cross Blue Shield of Rhode Island | |
| OHW | Wellmark BCBS | |
| OHX | Blue Cross Blue Shield of Rhode Island | |
| OHY | Blue Cross Blue Shield of Michigan | |
| OHZ | Blue Cross Blue Shield of Rhode Island | |
| OIA | Blue Cross of Idaho | |
| OIB | Highmark BCBS of Pennsylvania | |
| OIC | Independence Blue Cross | |
| OID | Blue Cross of Idaho | |
| OIE | Unassigned | |
| OIF | Blue Cross of Idaho | |
| OIG | Highmark BCBS of Pennsylvania | |
| OIH | Blue Cross of Idaho | |
| OII | Blue Cross Blue Shield of Michigan | |
| OIJ | Blue Cross Blue Shield of Michigan | |
| OIK | Blue Cross Blue Shield of Michigan | |
| OIL | Highmark BCBS of Pennsylvania | |
| OIM | Independence Blue Cross | |
| OIN | Highmark BCBS of Pennsylvania | |
| OIO | Blue Cross Blue Shield of Michigan | |
| OIP | Blue Shield of California | |
| OIQ | Blue Cross Blue Shield of Michigan | |
| OIR | Highmark BCBS of Pennsylvania | |
| OIS | BCBS of Western New York | |
| OIT | Blue Cross Blue Shield of Michigan | |
| OIU | Blue Cross Blue Shield of Michigan | |
| OIV | Blue Cross Blue Shield of Michigan | |
| OIW | Blue Cross Blue Shield of Michigan | |
| OIX | Blue Cross Blue Shield of Michigan | |
| OIY | Blue Cross Blue Shield of Michigan | |
| OIZ | Blue Cross of California | |
| OJA | CareFirst BCBS | |
| OJB | CareFirst BCBS | |
| OJC | Wellmark BCBS | |
| OJD | Unassigned | |
| OJE | Blue Cross Blue Shield of Michigan | |
| OJF | Blue Cross Blue Shield of Michigan | |
| OJG | Anthem BCBS of Wisconsin | |
| OJH | Blue Cross Blue Shield of Georgia | |
| OJI | Blue Cross Blue Shield of Michigan | |
| OJJ | Blue Cross Blue Shield of Michigan | |
| OJK | Blue Cross Blue Shield of Michigan | |
| OJL | Blue Cross Blue Shield of Michigan | |
| OJM | Anthem BCBS of Missouri | |
| OJN | Blue Cross Blue Shield of Michigan | |
| OJO | Blue Cross Blue Shield of Michigan | |
| OJP | Blue Cross Blue Shield of Rhode Island | |
| OJQ | Blue Cross Blue Shield of Michigan | |
| OJR | Wellmark BCBS | |
| OJS | CareFirst BCBS | |
| OJT | CareFirst BCBS | |
| OJU | Unassigned | |
| OJV | Blue Cross Blue Shield of Michigan | |
| OJW | Regence Blue Cross Blue Shield of Oregon | |
| OJX | Blue Cross Blue Shield of Michigan | |
| OJY | Blue Cross Blue Shield of Michigan | |
| OJZ | Blue Cross Blue Shield of Michigan | |
| OKA | Blue Cross Blue Shield of Michigan | |
| OKB | CareFirst BCBS | |
| OKC | Blue Cross Blue Shield of Oklahoma | |
| OKD | Independence Blue Cross | |
| OKE | CareFirst BCBS | |
| OKF | Blue Cross Blue Shield of Michigan | |
| OKG | Blue Cross Blue Shield of Michigan | |
| OKH | Blue Cross of California | |
| OKI | Blue Cross Blue Shield of Michigan | |
| OKJ | Blue Cross Blue Shield of Michigan | |
| OKK | Blue Cross Blue Shield of Michigan | |
| OKL | Blue Cross Blue Shield of Arkansas | |
| OKM | Independence Blue Cross | |
| OKN | Blue Cross Blue Shield of Michigan | |
| OKO | Blue Cross Blue Shield of Michigan | |
| OKP | Independence Blue Cross | |
| OKQ | Blue Cross Blue Shield of Michigan | |
| OKR | Anthem BCBS of Colorado | |
| OKS | BCBS of Western New York | |
| OKT | Anthem BCBS of Ohio | |
| OKU | Blue Cross Blue Shield of Michigan | |
| OKV | Blue Cross Blue Shield of Michigan | |
| OKW | Blue Cross of California | |
| OKX | Blue Cross Blue Shield of Michigan | |
| OKY | Blue Cross Blue Shield of Michigan | |
| OKZ | Blue Cross Blue Shield of Michigan | |
| OLA | Blue Cross Blue Shield of Kansas City | |
| OLB | Wellmark BCBS | |
| OLC | Unassigned | |
| OLD | Blue Shield of California | |
| OLE | Unassigned | |
| OLF | Blue Cross of California | |
| OLG | Premera Blue Cross | |
| OLH | Blue Cross Blue Shield of Arizona |
| OLI | Blue Cross Blue Shield of Michigan |
| OLJ | Unassigned |
| OLK | BCBS of Tennessee |
| OLL | CareFirst BCBS |
| OLM | Blue Cross Blue Shield of Arkansas |
| OLN | Blue Cross Blue Shield of Alabama |
| OLO | Blue Shield of California |
| OLP | BCBS of Western New York |
| OLQ | Blue Cross Blue Shield of Michigan |
| OLR | Blue Cross Blue Shield of South Carolina |
| OLS | CareFirst BCBS |
| OLT | Wellmark BCBS |
| OLU | Anthem BCBS of Colorado |
| OLV | Blue Cross Blue Shield of Michigan |
| OLW | BCBS of Western New York |
| OLX | Blue Cross Blue Shield of Michigan |
| OLY | Blue Cross Blue Shield of Michigan |
| OLZ | Blue Cross Blue Shield of Michigan |
| OMA | Anthem BCBS of Ohio |
| OMB | Anthem BCBS of Ohio |
| OMC | Unassigned |
| OMD | Independence Blue Cross |
| OME | Wellmark BCBS |
| OMF | Blue Cross of California |
| OMG | Blue Cross Blue Shield of Michigan |
| OMH | Blue Shield of California |
| OMI | Blue Cross Blue Shield of Georgia |
| OMJ | Independence Blue Cross |
| OMK | Anthem BCBS of Missouri |
| OML | BCBS of Florida |
| OMM | Blue Cross of California |
| OMN | Blue Cross of California |
| OMO | Blue Shield of California |
| OMP | Blue Cross Blue Shield of Michigan |
| OMQ | Blue Cross Blue Shield of Massachusetts |
| OMR | Blue Cross Blue Shield of Rhode Island |
| OMS | Blue Cross Blue Shield of Massachusetts |
| OMT | Blue Cross Blue Shield of Michigan |
| OMU | Blue Cross of Idaho |
| OMV | CareFirst BCBS |
| OMW | Blue Cross Blue Shield of Nebraska |
| OMX | Anthem BCBS of Colorado |
| OMY | Blue Cross Blue Shield of Vermont |
| OMZ | Blue Shield of California |
| ONA | Anthem BCBS of Missouri |
| ONB | Anthem BCBS of Ohio |
| ONC | Anthem BCBS of Indiana |
| OND | Wellmark BCBS |
| ONE | Anthem BCBS of Indiana |
| ONF | CareFirst BCBS |
| ONG | Blue Cross Blue Shield of Massachusetts |
| ONH | Blue Cross Blue Shield of Minnesota |
| ONI | Anthem BCBS of Indiana |
| ONJ | Wellmark BCBS |
| ONK | CareFirst BCBS |
| ONL | Anthem BCBS of Ohio |
| ONM | Unassigned |
| ONN | Blue Cross Blue Shield of South Carolina |
| ONO | Blue Shield of California |
| ONP | Anthem BCBS of Missouri |
| ONQ | Blue Cross Blue Shield of Alabama |
| ONR | Unassigned |
| ONS | Blue Cross Blue Shield of Alabama |
| ONT | Blue Cross Blue Shield of Massachusetts |
| ONU | CareFirst BCBS |
| ONV | CareFirst BCBS |
| ONW | Anthem BCBS of Indiana |
| ONX | Anthem BCBS of Indiana |
| ONY | Blue Cross Blue Shield of Minnesota |
| ONZ | Anthem BCBS of Indiana |
| OOA | Blue Shield of California |
| OOB | Blue Shield of California |
| OOC | Blue Cross Blue Shield of Massachusetts |
| OOD | BCBS of Michigan |
| OOE | Blue Cross Blue Shield of Michigan |
| OOF | BCBS of Michigan |
| OOG | Blue Shield of California |
| OOH | Independence Blue Cross |
| OOI | BCBS of Michigan |
| OOJ | Blue Cross Blue Shield of Michigan |
| OOK | Blue Cross Blue Shield of Michigan |
| OOL | Blue Cross Blue Shield of Rhode Island |
| OOM | Blue Cross of California |
| OON | Blue Cross Blue Shield of Michigan |
| OOO | Blue Cross Blue Shield of Michigan |
| OOP | Blue Shield of California |
| OOQ | Blue Cross Blue Shield of Michigan |
| OOR | Blue Cross Blue Shield of North Carolina |
| OOS | Blue Shield of California |
| OOT | Blue Shield of California |
| OOU | Blue Cross Blue Shield of Michigan |
| OOV | BCBS of Michigan |
| OOW | BCBS of Michigan |
| OOX | Blue Cross Blue Shield of Michigan |
| OOY | Unassigned |
| OOZ | Blue Cross Blue Shield of Michigan |
| OPA | Blue Cross Blue Shield of Louisiana |
| OPB | Highmark BCBS of Pennsylvania |
| OPC | Blue Cross Blue Shield of Oklahoma |
| OPD | Blue Cross Blue Shield of Wisconsin |
| OPE | Blue Cross Blue Shield of Georgia | |
| OPF | Anthem BCBS of Wisconsin | |
| OPG | Blue Cross of California | |
| OPH | CareFirst BCBS | |
| OPI | Blue Cross Blue Shield of North Carolina | |
| OPJ | Anthem BCBS of Wisconsin | |
| OPK | Anthem BCBS of Wisconsin | |
| OPL | Blue Cross Blue Shield of Georgia | |
| OPM | Blue Cross Blue Shield of Georgia | |
| OPN | Blue Cross Blue Shield of Michigan | |
| OPO | Unassigned | |
| OPP | Wellmark BCBS | |
| OPQ | Premera Blue Cross | |
| OPR | Wellmark BCBS | |
| OPS | Blue Cross Blue Shield of Massachusetts | |
| OPT | CareFirst BCBS | |
| OPU | Anthem BCBS of Wisconsin | |
| OPV | Anthem BCBS of Wisconsin | |
| OPW | Anthem BCBS of Wisconsin | |
| OPX | Anthem BCBS of Wisconsin | |
| OPY | Independence Blue Cross | |
| OPZ | Anthem BCBS of Wisconsin | |
| OQA | Anthem BCBS of Ohio | |
| OQB | Blue Cross of California | |
| OQC | Independence Blue Cross | |
| OQD | Blue Cross Blue Shield of Michigan | |
| OQE | Blue Cross Blue Shield of Michigan | |
| OQF | Blue Cross Blue Shield of Michigan | |
| OQG | Blue Cross Blue Shield of Michigan | |
| OQH | Blue Cross Blue Shield of Michigan | |
| OQI | Blue Cross Blue Shield of Michigan | |
| OQJ | Blue Cross Blue Shield of Michigan | |
| OQK | Blue Cross Blue Shield of Michigan | |
| OQL | Blue Cross Blue Shield of Michigan | |
| OQM | Blue Cross Blue Shield of Michigan | |
| OQN | Blue Cross Blue Shield of Michigan | |
| OQO | Blue Cross Blue Shield of Michigan | |
| OQP | Blue Cross of California | |
| OQQ | Blue Cross Blue Shield of Michigan | |
| OQR | Blue Cross Blue Shield of Michigan | |
| OQS | Blue Cross of California | |
| OQT | Blue Cross Blue Shield of Michigan | |
| OQU | Blue Cross Blue Shield of Michigan | |
| OQV | Blue Cross Blue Shield of Michigan | |
| OQW | Blue Cross Blue Shield of Michigan | |
| OQX | Unassigned | |
| OQY | Unassigned | |
| OQZ | Unassigned | |
| ORA | Wellmark BCBS | |
| ORB | Wellmark BCBS | |
| ORC | Anthem BCBS of Kentucky | |
| ORD | Independence Blue Cross | |
| ORE | BCBS of Tennessee | |
| ORF | Blue Cross Blue Shield of Michigan | |
| ORG | CareFirst BCBS | |
| ORH | Anthem BCBS of Missouri | |
| ORI | Blue Cross Blue Shield of South Carolina | |
| ORJ | Blue Cross Blue Shield of Michigan | |
| ORK | Anthem BCBS of Ohio | |
| ORL | Blue Cross of California | |
| ORM | Blue Shield of Northeastern New York | |
| ORN | Horizon Blue Cross Blue Shield of New Jersey | |
| ORO | Blue Cross Blue Shield of Michigan | |
| ORP | Blue Cross of California | |
| ORQ | Blue Cross Blue Shield of Michigan | |
| ORR | Unassigned | |
| ORS | Regence Blue Shield of Washington | |
| ORT | Capital BlueCross | |
| ORU | BCBS of Tennessee | |
| ORV | Blue Cross Blue Shield of Michigan | |
| ORW | Anthem BCBS of Virginia | |
| ORX | Blue Cross of Idaho | |
| ORY | Blue Shield of California | |
| ORZ | Horizon Blue Cross Blue Shield of New Jersey | |
| OSA | Blue Cross Blue Shield of Rhode Island | |
| OSB | Blue Cross Blue Shield of Alabama | |
| OSC | Blue Shield of California | |
| OSD | Blue Cross Blue Shield of Massachusetts | |
| OSE | Blue Cross Blue Shield of Arizona | |
| OSF | Blue Cross Blue Shield of Rhode Island | |
| OSG | Blue Cross Blue Shield of Missouri | |
| OSH | CareFirst BCBS | |
| OSI | Independence Blue Cross | |
| OSJ | Anthem BCBS of Ohio | |
| OSK | Blue Cross of California | |
| OSL | Blue Cross Blue Shield of Nebraska | |
| OSM | Blue Cross Blue Shield of Illinois | |
| OSN | Anthem BCBS of Ohio | |
| OSO | Independence Blue Cross | |
| OSP | BCBS of Florida | |
| OSQ | Highmark BCBS of Pennsylvania | |
| OSR | Independence Blue Cross | |
| OSS | Blue Shield of California | |
| OST | Highmark BCBS of Pennsylvania | |
| OSU | Blue Shield of California | |
| OSV | Independence Blue Cross | |
| OSW | Wellmark BCBS | |
| OSX | Wellmark BCBS | |
| OSY | Blue Cross Blue Shield of Kansas City | |
| OSZ | Anthem BCBS of Virginia |
| OTA | BCBS of Florida | |
| OTB | Empire Blue Cross Blue Shield | |
| OTC | Blue Cross Blue Shield of Nebraska | |
| OTD | Blue Cross of California | |
| OTE | Anthem BCBS of Indiana | |
| OTF | Anthem BCBS of Indiana | |
| OTG | Blue Cross Blue Shield of Michigan | |
| OTH | BCBS of Tennessee | |
| OTI | Blue Cross Blue Shield of North Dakota | |
| OTJ | CareFirst BCBS | |
| OTK | Wellmark BCBS | |
| OTL | Blue Cross Blue Shield of Alabama | |
| OTM | Blue Shield of California | |
| OTN | Blue Cross Blue Shield of North Dakota | |
| OTO | Blue Cross Blue Shield of North Dakota | |
| OTP | Blue Shield of California | |
| OTQ | Anthem BCBS of Connecticut | |
| OTR | Unassigned | |
| OTS | Independence Blue Cross | |
| OTT | Wellmark BCBS | |
| OTU | Wellmark BCBS | |
| OTV | Capital BlueCross | |
| OTW | Blue Cross Blue Shield of Georgia | |
| OTX | Blue Shield of California | |
| OTY | Regence Blue Cross Blue Shield of Oregon | |
| OTZ | Anthem BCBS of Ohio | |
| OUA | Regence Blue Cross Blue Shield of Oregon | |
| OUB | Blue Cross Blue Shield of Rhode Island | |
| OUC | Blue Cross Blue Shield of South Carolina | |
| OUD | Blue Cross Blue Shield of Michigan | |
| OUE | Blue Cross Blue Shield of Rhode Island | |
| OUF | Regence Blue Cross Blue Shield of Oregon | |
| OUG | Blue Cross Blue Shield of Rhode Island | |
| OUH | Empire Blue Cross Blue Shield | |
| OUI | Horizon Blue Cross Blue Shield of New Jersey | |
| OUJ | Blue Cross Blue Shield of Michigan | |
| OUK | Blue Cross Blue Shield of Michigan | |
| OUL | Blue Cross Blue Shield of Michigan | |
| OUM | Blue Cross Blue Shield of Michigan | |
| OUN | Blue Cross Blue Shield of Michigan | |
| OUO | Blue Cross Blue Shield of Michigan | |
| OUP | Wellmark BCBS | |
| OUQ | Blue Cross Blue Shield of Michigan | |
| OUR | Horizon Blue Cross Blue Shield of New Jersey | |
| OUS | Highmark BCBS of Pennsylvania | |
| OUT | Horizon Blue Cross Blue Shield of New Jersey | |
| OUU | Blue Cross Blue Shield of Michigan | |
| OUV | Blue Cross Blue Shield of Michigan | |
| OUW | Highmark BCBS of Pennsylvania | |
| OUX | Blue Cross Blue Shield of Michigan | |
| OUY | Blue Cross Blue Shield of Michigan | |
| OUZ | Blue Cross Blue Shield of Michigan | |
| OVA | Anthem BCBS of Ohio | |
| OVB | CareFirst BCBS | |
| OVC | Independence Blue Cross | |
| OVD | Blue Cross Blue Shield of Michigan | |
| OVE | Blue Cross of California | |
| OVF | CareFirst BCBS | |
| OVG | Blue Cross Blue Shield of Michigan | |
| OVH | Premera Blue Cross | |
| OVI | Blue Cross Blue Shield of Michigan | |
| OVJ | Unassigned | |
| OVK | Blue Cross Blue Shield of Georgia | |
| OVL | BCBS of Western New York | |
| OVM | Wellmark BCBS | |
| OVN | Blue Cross Blue Shield of Michigan | |
| OVO | Blue Cross Blue Shield of Michigan | |
| OVP | Anthem BCBS of Ohio | |
| OVQ | Blue Cross Blue Shield of Michigan | |
| OVR | CareFirst BCBS | |
| OVS | Anthem BCBS of Ohio | |
| OVT | Anthem BCBS of Ohio | |
| OVU | Blue Cross Blue Shield of Michigan | |
| OVV | Blue Cross Blue Shield of Michigan | |
| OVW | Highmark BCBS of Pennsylvania | |
| OVX | Blue Cross Blue Shield of Michigan | |
| OVY | Blue Cross Blue Shield of Michigan | |
| OVZ | Blue Cross Blue Shield of Michigan | |
| OWA | Wellmark BCBS | |
| OWB | CareFirst BCBS | |
| OWC | Regence Blue Cross Blue Shield of Oregon | |
| OWD | CareFirst BCBS | |
| OWE | BCBS of Florida | |
| OWF | Wellmark BCBS | |
| OWG | BCBS of Western New York | |
| OWH | Anthem BCBS of Connecticut | |
| OWI | Anthem BCBS of Ohio | |
| OWJ | Anthem BCBS of Virginia | |
| OWK | Blue Cross Blue Shield of Michigan | |
| OWL | Blue Shield of California | |
| OWM | Unassigned | |
| OWN | Unassigned | |
| OWO | Blue Cross Blue Shield of Michigan | |
| OWP | Empire Blue Cross Blue Shield | |
| OWQ | Blue Cross Blue Shield of Michigan | |
| OWR | Blue Cross Blue Shield of Michigan | |
| OWS | Anthem BCBS of Virginia | |
| OWT | Blue Cross Blue Shield of Georgia | |
| OWU | Blue Cross Blue Shield of Michigan | |
| OWV | Highmark BCBS of Pennsylvania |
| OWW | Anthem BCBS of Virginia | |
| OWX | Anthem BCBS of Ohio | |
| OWY | Empire Blue Cross Blue Shield | |
| OWZ | Wellmark BCBS | |
| OXA | BCBS of Western New York | |
| OXB | Regence Blue Cross Blue Shield of Oregon | |
| OXC | Premera Blue Cross | |
| OXD | Blue Cross of California | |
| OXE | Blue Cross Blue Shield of Michigan | |
| OXF | Unassigned | |
| OXG | Blue Cross Blue Shield of Michigan | |
| OXH | Blue Cross Blue Shield of Michigan | |
| OXI | Blue Cross Blue Shield of Michigan | |
| OXJ | Blue Cross Blue Shield of Michigan | |
| OXK | Blue Cross Blue Shield of Michigan | |
| OXL | Blue Cross Blue Shield of Michigan | |
| OXM | Premera Blue Cross | |
| OXN | Regence Blue Cross Blue Shield of Oregon | |
| OXO | BCBS of Western New York | |
| OXP | Blue Cross of California | |
| OXQ | Blue Cross Blue Shield of Michigan | |
| OXR | Blue Cross Blue Shield of Michigan | |
| OXS | Blue Shield of California | |
| OXT | Blue Cross Blue Shield of Michigan | |
| OXU | Blue Cross Blue Shield of Michigan | |
| OXV | Blue Cross Blue Shield of Michigan | |
| OXW | Blue Cross Blue Shield of Michigan | |
| OXX | Blue Cross Blue Shield of Michigan | |
| OXY | Blue Cross Blue Shield of Michigan | |
| OXZ | Unassigned | |
| OYA | Wellmark BCBS | |
| OYB | Blue Cross of California | |
| OYC | Horizon Blue Cross Blue Shield of New Jersey | |
| OYD | Blue Cross of Idaho | |
| OYE | Wellmark BCBS | |
| OYF | Blue Cross Blue Shield of Michigan | |
| OYG | Blue Cross Blue Shield of Michigan | |
| OYH | Anthem BCBS of Ohio | |
| OYI | Blue Cross Blue Shield of Michigan | |
| OYJ | Blue Cross Blue Shield of Michigan | |
| OYK | Blue Cross Blue Shield of Michigan | |
| OYL | Blue Shield of California | |
| OYM | Independence Blue Cross | |
| OYN | Blue Cross Blue Shield of Michigan | |
| OYO | Blue Cross Blue Shield of Michigan | |
| OYP | Blue Cross Blue Shield of Georgia | |
| OYQ | Blue Cross Blue Shield of Michigan | |
| OYR | Blue Cross Blue Shield of Michigan | |
| OYS | Blue Shield of California | |
| OYT | Blue Cross Blue Shield of Michigan | |
| OYU | Blue Cross Blue Shield of Michigan | |
| OYV | Unassigned | |
| OYW | Blue Cross Blue Shield of Michigan | |
| OYX | Blue Cross Blue Shield of Michigan | |
| OYY | Blue Cross Blue Shield of Michigan | |
| OYZ | BCBS of Tennessee | |
| OZA | Anthem BCBS of Missouri | |
| OZB | Anthem BCBS of Wisconsin | |
| OZC | Horizon Blue Cross Blue Shield of New Jersey | |
| OZD | Anthem BCBS of Virginia | |
| OZE | Blue Cross Blue Shield of Michigan | |
| OZF | Blue Cross Blue Shield of Michigan | |
| OZG | Blue Shield of California | |
| OZH | Capital BlueCross | |
| OZI | Blue Cross Blue Shield of Michigan | |
| OZJ | Blue Cross Blue Shield of Michigan | |
| OZK | Anthem BCBS of Missouri | |
| OZL | Blue Cross Blue Shield of Michigan | |
| OZM | Anthem BCBS of Virginia | |
| OZN | Blue Cross Blue Shield of Michigan | |
| OZO | Blue Cross Blue Shield of Michigan | |
| OZP | Blue Cross of California | |
| OZQ | Blue Cross Blue Shield of Michigan | |
| OZR | Blue Cross Blue Shield of Michigan | |
| OZS | BCBS of Western New York | |
| OZT | Blue Cross Blue Shield of Michigan | |
| OZU | Blue Cross Blue Shield of Michigan | |
| OZV | Blue Cross Blue Shield of Michigan | |
| OZW | Blue Cross Blue Shield of Georgia | |
| OZX | Anthem BCBS of Missouri | |
| OZY | Blue Cross Blue Shield of Michigan | |
| OZZ | Blue Cross Blue Shield of Michigan |