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The world's largest debt collection operation will pay a $3.2 million civil penalty, the largest ever obtained by the Federal Trade Commission against a third-party debt collector, for illegally harassing debtors.

Under the settlement, the FTC said Expert Global Solutions and its subsidiaries agreed to stop harassing consumers with illegal debt collection calls, including calling consumers multiple times a day and at workplaces, even after being told that employers prohibited these calls.

In its complaint, the FTC charged that the companies violated the Fair Debt Collection Practices Act and the FTC Act by using other tactics such as calling early in the morning or late at night, and leaving phone messages that disclosed the debtor's name and the existence of the debt to third parties.

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Expert Global Solutions and its subsidiaries, based in Texas, has more than 32,000 employees and revenue in 2011 of more than $1.2 billion. The subsidiaries include ALW Sourcing, LLC; NCO Financial Systems, Inc.; and Transworld Systems, Inc., which also does business as North Shore Agency, Inc. They are collectively the largest debt collector in the world. The companies also operate in Canada, Barbados, India, the Philippines and Panama.

A spokesman for EGS provided a statement to ABC News, saying, "We are pleased to have resolved this matter with the Federal Trade Commission (FTC) and to have this legacy issue, dating back to 2008, behind us. We cooperated fully with the FTC's 2010 investigation and have already implemented systems and procedures to help address their areas of concern."

They added, "We believe that the quality of our consumer interaction is best-in-class in our industry today, and have worked hard over the past several years to help ensure compliance and fair treatment of consumers on all of our points of contact."

In this proposed order with the FTC, "whenever a consumer disputes the validity or the amount of the debt, the defendants must either close the account and end collection efforts, or suspend collection until they have conducted a reasonable investigation and verified that their information about the debt is accurate and complete," the commission said.

The defendants also are required to record at least 75 percent of their debt collection calls beginning one year after the date of the order, and retain the recordings for 90 days after they are made.

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