On Friday, Visa and MasterCard notified users of the potential for identity theft and illicit charges. Officials say cardholder names, addresses and social security numbers were not obtained.
Global Payments CEO Paul Garcia noted that the company continues to process Visa transactions, but that being dropped from the registry "could give our partners some pause that they're doing business with someone who experienced a breach."
Garcia said he expects to Global Payments to be reinstated once it has been issued a new report of compliance, adding that the investigation is ongoing even though the situation is contained.
Both Visa and MasterCard said their own systems weren't compromised.
In the meantime, a technical problem affecting Visa's network prevented people from using their credit and debit cards for a short time on Sunday. Visa says the problem was unrelated to the security breach.
The Associated Press contributed to this report.