| C2A | Blue Cross Blue Shield of Texas |
| C2B | Highmark Blue Cross Blue Shield of Delaware |
| C2C | Blue Shield of Northeastern New York |
| C2D | Anthem Blue Cross Blue Shield of Wisconsin |
| C2E | Premera Blue Cross |
| C2F | Highmark Blue Cross Blue Shield |
| C2G | Blue Cross Blue Shield of Minnesota |
| C2H | Blue Cross Blue Shield of Alabama |
| C2I | Highmark Blue Shield |
| C2J | Anthem Blue Cross of California |
| C2K | Blue Cross Blue Shield of Minnesota |
| C2L | Highmark Blue Cross Blue Shield |
| C2M | Anthem Blue Cross of California |
| C2N | Highmark Blue Cross Blue Shield |
| C2O | Independence Blue Cross |
| C2P | Blue Cross Blue Shield of Illinois |
| C2Q | Independence Blue Cross |
| C2R | Blue Cross Blue Shield of Illinois |
| C2S | Blue Cross Blue Shield of Illinois |
| C2T | Blue Cross Blue Shield of Alabama |
| C2U | Highmark Blue Cross Blue Shield |
| C2V | Premera Blue Cross |
| C2W | Regence Blue Cross Blue Shield |
| C2X | Carefirst Blue Cross Blue Shield |
| C2Y | Blue Cross Blue Shield of Minnesota |
| C2Z | Anthem Blue Cross of California |
| C3A | Regence Blue Cross Blue Shield |
| C3B | Anthem Blue Cross Blue Shield of Wisconsin |
| C3C | Regence Blue Cross Blue Shield |
| C3D | Premera Blue Cross |
| C3E | Blue Cross Blue Shield of Texas |
| C3F | Highmark Blue Cross Blue Shield of Delaware |
| C3G | Anthem Blue Cross of California |
| C3H | Blue Cross Blue Shield of Alabama |
| C3I | Unassigned Prefix |
| C3J | Anthem Blue Cross Blue Shield of Indiana |
| C3K | Highmark Blue Cross Blue Shield |
| C3L | Highmark Blue Cross Blue Shield |
| C3M | Highmark Blue Cross Blue Shield |
| C3N | Blue Cross Blue Shield of Texas |
| C3O | Anthem Blue Cross Blue Shield of Virginia |
| C3P | Premera Blue Cross |
| C3Q | Blue Cross Blue Shield of Michigan |
| C3R | Highmark Blue Cross Blue Shield |
| C3S | Anthem Blue Cross Blue Shield of Virginia |
| C3T | Regence Blue Cross Blue Shield |
| C3U | Anthem Blue Cross Blue Shield of Wisconsin |
| C3V | Blue Cross Blue Shield of Illinois |
| C3W | Regence Blue Cross Blue Shield |
| C3X | Anthem Blue Cross Blue Shield of Wisconsin |
| C3Y | Empire Blue Cross Blue Shield |
| C3Z | Empire Blue Cross Blue Shield |
| C4A | Premera Blue Cross Blue Shield of Alaska |
| C4B | Anthem Blue Cross Blue Shield of Virginia |
| C4C | Blue Cross Blue Shield of Texas |
| C4D | Empire Blue Cross Blue Shield |
| C4E | Independence Blue Cross |
| C4F | Anthem Blue Cross Blue Shield of Virginia |
| C4G | Anthem Blue Cross Blue Shield of New Hampshire |
| C4H | Regence Blue Cross Blue Shield |
| C4I | Highmark Blue Cross Blue Shield of Western New York |
| C4J | Horizon Blue Cross Blue Shield |
| C4K | Highmark Blue Cross Blue Shield |
| C4L | Blue Cross Blue Shield of Texas |
| C4M | Empire Blue Cross Blue Shield |
| C4N | Independence Blue Cross |
| C4O | Unassigned Prefix |
| C4P | Blue Cross Blue Shield of Texas |
| C4Q | Independence Blue Cross |
| C4R | Premera Blue Cross Blue Shield of Alaska |
| C4S | Carefirst Blue Cross Blue Shield |
| C4T | Anthem Blue Cross Blue Shield of Ohio |
| C4U | Blue Cross Blue Shield of Oklahoma |
| C4V | Anthem Blue Cross Blue Shield of Georgia |
| C4W | Blue Cross Blue Shield of Western New York |
| C4X | Blue Cross Blue Shield of Texas |
| C4Y | Blue Cross Blue Shield of Texas |
| C4Z | Blue Cross Blue Shield of Tennessee |
| C5A | Anthem Blue Cross of California |
| C5B | Blue Cross Blue Shield of Illinois |
| C5C | Arkansas Blue Cross |
| C5D | Blue Cross Blue Shield of Illinois |
| C5E | Highmark Blue Cross Blue Shield |
| C5F | Blue Cross Blue Shield of Texas |
| C5G | Anthem Blue Cross Blue Shield of Indiana |
| C5H | Anthem Blue Cross Blue Shield of Indiana |
| C5I | Unassigned Prefix |
| C5J | Anthem Blue Cross Blue Shield of Indiana |
| C5K | Blue Shield of Northeastern New York |
| C5L | Blue Cross Blue Shield of Illinois |
| C5M | Anthem Blue Cross Blue Shield of Georgia |
| C5N | Blue Cross Blue Shield of Illinois |
| C5O | Unassigned Prefix |
| C5P | Carefirst Blue Cross Blue Shield |
| C5Q | Independence Blue Cross |
| C5R | Anthem Blue Cross Blue Shield of Connecticut |
| C5S | Anthem Blue Cross Blue Shield of Colorado |
| C5T | Anthem Blue Cross Blue Shield of Missouri |
| C5U | Anthem Blue Cross Blue Shield of Colorado |
| C5V | Blue Cross Blue Shield of Texas |
| C5W | Anthem Blue Cross Blue Shield of Georgia |
| C5X | Anthem Blue Cross Blue Shield of Colorado |
| C5Y | Blue Cross Blue Shield of Oklahoma |
| C5Z | Blue Cross Blue Shield of Western New York |
| C6A | Anthem Blue Cross of California |
| C6B | Anthem Blue Cross Blue Shield of New Hampshire |
| C6C | Anthem Blue Cross Blue Shield of Virginia |
| C6D | Anthem Blue Cross Blue Shield of New Hampshire |
| C6E | Anthem Blue Cross Blue Shield of New Hampshire |
| C6F | Blue Cross Blue Shield of Illinois |
| C6G | Anthem Blue Cross Blue Shield of New Hampshire |
| C6H | Anthem Blue Cross Blue Shield of Virginia |
| C6I | Unassigned Prefix |
| C6J | Blue Cross Blue Shield of Illinois |
| C6K | Anthem Blue Cross Blue Shield of Indiana |
| C6L | Horizon Blue Cross Blue Shield |
| C6M | Blue Cross Blue Shield of Michigan |
| C6N | Blue Cross Blue Shield of Illinois |
| C6O | Unassigned Prefix |
| C6P | Regence Blue Cross Blue Shield |
| C6Q | Independence Blue Cross |
| C6R | Empire Blue Cross Blue Shield |
| C6S | Anthem Blue Cross Blue Shield of Virginia |
| C6T | Regence Blue Cross Blue Shield |
| C6U | Blue Cross Blue Shield of Illinois |
| C6V | Regence Blue Cross Blue Shield |
| C6W | Anthem Blue Cross Blue Shield of Georgia |
| C6X | Anthem Blue Cross Blue Shield of Connecticut |
| C6Y | Anthem Blue Cross Blue Shield of Virginia |
| C6Z | Anthem Blue Cross Blue Shield of Indiana |
| C7A | Anthem Blue Cross of California |
| C7B | Blue Cross Blue Shield of Illinois |
| C7C | Blue Cross Blue Shield of Minnesota |
| C7D | Blue Cross Blue Shield of Illinois |
| C7E | Anthem Blue Cross Blue Shield of Colorado |
| C7F | Blue Cross Blue Shield of Illinois |
| C7G | Unassigned Prefix |
| C7H | Blue Cross Blue Shield of Illinois |
| C7I | Unassigned Prefix |
| C7J | Unassigned Prefix |
| C7K | Anthem Blue Cross Blue Shield of Colorado |
| C7L | Blue Cross Blue Shield of Illinois |
| C7M | Anthem Blue Cross Blue Shield of Wisconsin |
| C7N | Anthem Blue Cross Blue Shield of Wisconsin |
| C7O | Regence Blue Cross Blue Shield |
| C7P | Carefirst Blue Cross Blue Shield |
| C7Q | Anthem Blue Cross Blue Shield of Georgia |
| C7R | Blue Cross Blue Shield of Texas |
| C7S | Blue Cross Blue Shield of Minnesota |
| C7T | Anthem Blue Cross Blue Shield of Ohio |
| C7U | Blue Cross Blue Shield of Illinois |
| C7V | Blue Cross Blue Shield of Texas |
| C7W | Anthem Blue Cross Blue Shield of Colorado |
| C7X | Anthem Blue Cross Blue Shield of Colorado |
| C7Y | Regence Blue Cross Blue Shield |
| C7Z | Carefirst Blue Cross Blue Shield |
| C8A | Anthem Blue Cross of California |
| C8B | Blue Cross Blue Shield of Illinois |
| C8C | Anthem Blue Cross Blue Shield of Missouri |
| C8D | Anthem Blue Cross Blue Shield of Missouri |
| C8E | Anthem Blue Cross Blue Shield of Nevada |
| C8F | Blue Cross of Massachusetts |
| C8G | Regence Blue Cross Blue Shield |
| C8H | Blue Cross Blue Shield of Illinois |
| C8I | Unassigned Prefix |
| C8J | Horizon Blue Cross Blue Shield |
| C8K | Anthem Blue Cross Blue Shield of Nevada |
| C8L | Carefirst Blue Cross Blue Shield |
| C8M | Blue Cross Blue Shield of Illinois |
| C8N | Blue Cross Blue Shield of Illinois |
| C8O | Unassigned Prefix |
| C8P | Blue Cross Blue Shield of Texas |
| C8Q | Unassigned Prefix |
| C8R | Blue Cross Blue Shield of Texas |
| C8S | Blue Cross Blue Shield of Minnesota |
| C8T | Anthem Blue Cross Blue Shield of Nevada |
| C8U | Anthem Blue Cross Blue Shield of Connecticut |
| C8V | Anthem Blue Cross of California |
| C8W | Blue Cross of Massachusetts |
| C8X | Independence Blue Cross |
| C8Y | Carefirst Blue Cross Blue Shield |
| C8Z | Anthem Blue Cross Blue Shield of Connecticut |
| C9A | Blue Cross Blue Shield of Western New York |
| C9B | Anthem Blue Cross Blue Shield of Connecticut |
| C9C | Anthem Blue Cross Blue Shield of Connecticut |
| C9D | Regence Blue Cross Blue Shield |
| C9E | Anthem Blue Cross of California |
| C9F | Anthem Blue Cross Blue Shield of Nevada |
| C9G | Carefirst Blue Cross Blue Shield |
| C9H | Blue Cross Blue Shield of Illinois |
| C9I | Highmark Blue Cross Blue Shield of Delaware |
| C9J | Horizon Blue Cross Blue Shield |
| C9K | Horizon Blue Cross Blue Shield |
| C9L | Horizon Blue Cross Blue Shield |
| C9M | Anthem Blue Cross Blue Shield of Connecticut |
| C9N | Blue Cross Blue Shield of Illinois |
| C9O | Highmark Blue Cross Blue Shield of Delaware |
| C9P | Blue Cross Blue Shield of Texas |
| C9Q | Horizon Blue Cross Blue Shield |
| C9R | Blue Cross Blue Shield of Texas |
| C9S | Premera Blue Cross Blue Shield of Alaska |
| C9T | Anthem Blue Cross Blue Shield of Connecticut |
| C9U | Horizon Blue Cross Blue Shield |
| C9V | Horizon Blue Cross Blue Shield |
| C9W | Carefirst Blue Cross Blue Shield |
| C9X | Anthem Blue Cross Blue Shield of Colorado |
| C9Y | Empire Blue Cross Blue Shield |
| C9Z | Blue Cross Blue Shield of Texas |
