The administration has finally announced the error rate for 834 transmissions, the data sent to insurance companies after applicants fill out their information on the Healthcare.gov marketplace. 834 is short for 834 Electronic Data Interchange Transmissions or 834 EDI Transactions, the files that get passed to insurance companies so new enrollees can be added to their systems. Insurance companies have reported errors since the site launched Insurance companies have reported 834 errors since the site launched, saying they had to call applicants to manually verify information.