Another company has also sued Apple, this time for allegedly infringing a patent described as 'Wireless Mobile Phone Including a Headset'.

The $3 million patent-infringement lawsuit was filed by Intelligent Smart Phones Concepts.

The patent describes an interface that allows a removable headset "to receive at least telephony audio signals from the phone, and to provide audio signals to the phone."

ISPC is asking for $3 million to compensate for lost revenue and royalties. The company also wants an injunction preventing Apple from further infringement of the patent.

Cnet suggests that the company that filed the lawsuit is a 'patent troll'.

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