The injunction orders Seemab Zafar to hand over any part of the database of the former C&W Bulldog subsidiary, reports the BBC.
Zafar has denied she holds any part of the database, which is believed to have been used to make calls to customers from call centres based in Pakistan.
The call centres are said to have tricked Bulldog customers into handing over credit card details.
C&W brought the injunction as it owned Bulldog when the database was allegedly stolen. Last September, C&W sold Bulldog to Pipex.
Zafar is now said to run an international outsourcing business. Zafar has told the BBC she has no part of the database.
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