Cable & Wireless has served an injunction against a former executive following the theft of a 100,000 customer database, the BBC has learned.
The injunction orders Seemab Zafar to hand over any part of the database of former subsidiary Bulldog, including names, addresses and financial details.
Ms Zafar, from London, denies that she holds any part of the database.
A BBC investigation has established that the database had been illegally used by call centres in Pakistan.
The call centres tricked customers into handing over credit card details.
One victim of the scam, Gareth Thomas, has subsequently been defrauded on his bank and credit cards, and had his identity cloned on the internet pay system Paypal.
Other victims complained of being relentlessly called by call centres in South East Asia, who won't reveal their identity nor what personal information they hold.
The High Court injunction was brought by Cable & Wireless because it owned internet services provider Bulldog at the time the database was taken.
The data base of up to 100,000 names was stolen at the same time as an employee went on a business trip to Pakistan in 2005.
Cable & Wireless said "the employee did not return as planned and was then sacked", adding that "we take this matter very seriously".
Ms Zafar now runs an international out-sourcing business.
She recently emailed the BBC from abroad to deny that she had any part of the data base: "For the record I am letting you know that I do not have any part of the Bulldog database and this is exactly what I told the lawyers."
Cable & Wireless believe its injunction, served in the past few days, has "led to the destruction of all copies of the Bulldog customer data" that may have been in the possession of Ms Zafar and her companies.
But it declined to give any assurances that data which may have been passed to other call centres had also been destroyed.
Since September 2006 Bulldog is part of the Pipex Group.