The lawsuits stem from the affair in which HP used illegal pre-texting techniques to trace the source of information leaks from its board.
Cingular filed its suit against Charles Kelly and the CAS Agency, a private investigation firm hired by HP. Cingular also accused a group of unnamed individuals, whose identities it aims to acquire during the case's discovery process.
The operator accused the defendants of "unlawfully obtaining, disseminating or otherwise using Cingular's confidential customer information", according to the legal complaint filed on 29 September.
The incident relates to the phone records of CNet reporter Dawn Kawamoto. Investigators contacted Cingular's customer service posing as the account holder or as employees requiring urgent access to customer records or using the account holder's password to access Kawamoto's online account.
Cingular is demanding that the defendants return all confidential information, including information that they passed on to HP and any other parties.
It has also called for an injunction barring the defendants from gathering information in the future, as well as unspecified damages.
The Verizon lawsuit was filed on 28 September, the same day that HP chief executive Mark Hurd testified before a congressional committee about the affair.
The lawsuit alleges that people employed by HP called Verizon's customer service department posing as a company employee.
This resulted in the alleged disclosure of confidential information pertaining to one HP director and his spouse.
The information also allowed the investigator to log-in to the customer's account. Verizon is seeking unspecified damages as well as an injunction.
Verizon and Cingular are the first to file legal complaints in response to the HP spying scandal.
The case also has given a boost to legislation that will ban the use of pre-texting techniques. Although current legislation already prohibits the practice, revised legislation could define harsher penalties.
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