• Health claims clearinghouses

• Health insurers

• Value added networks

• Software vendors

• Health care data processing companies

• Practice management companies

• Data communications systems operators

• Credit card issuers

ADMINASTAR COMMUNICATIONS

Louisville, KY

ADMINISTRATIVE SERVICES OF KANSAS

Topeka, KS

AETNA INSURANCE COMPANY

Hartford, CT

BLUE CROSS OF CALIFORNIA

Woodland Hills, CA

BC/BS OF GEORGIA

Columbus, GA

CIS TECHNOLOGIES

Tulsa, OK

COMPUTERMART MEDICAL SERVICES

Jonesboro, GA

CONTEXT SOFTWARE INC

Burr Ridge, IL

CSC HEALTHCARE SYSTEMS

Farmington Hills, MI

DATAMEDIC CORPORATION

Hauppauge, NY

EDI - USA

Louisville, KY

EDS

Plano, TX

ENVOY CORPORATION

Nashville, TN

HEALTHCARE INTERCHANGE INC

St. Louis, MO

IBM GLOBAL NETWORK / ADVANTIS

Tampa, FL

IVANS

Tampa, FL

JOHN DEERE HEALTH CARE INC

Moline, IL

MASTERCARD INTERNATIONAL

Purchase, NY

MEDE AMERICA INC

Mitchell Field, NY

MEDIC COMPUTER SYSTEMS

Raleigh, NC

NATIONAL DATA CORPORATION

Atlanta, GA

OFFICE TECH INC.

Saint Louis, MO

PCS HEALTH SYSTEMS INC

Scottsdale, AZ

THE CENTRIS GROUP

Atlanta, GA

THE HEALTH INFORMATION NETWORK CONNECTION

New York, NY

VISA INTERNATIONAL

San Francisco, CA