Apple, AT&T and 31 others have been slammed with a patent infringement lawsuit scant hours since the patent in question was granted.

The US Patent Office last week granted a smart phone patent to LA patent-holding firm, Minerva Industries. That firm then laid the suit down against 33 firms for patent infringement on the same day as the patent was granted.

The patent is for a "mobile entertainment and communication device" that has "a cellular or satellite telephone capable of wireless communication with the internet."

The company has specifically accused Apple's iPhone of infringing on this retrospectively-granted patent, but says all 33 defendants in the case sell phones that are covered by it.

Patent experts believe the patent granted to be overly broad, making it highly likely the exercise of the patent will be opposed.

Apple, AT&T and others also face patent pressure from Klausner Technologies who claim to own the patent for the Visual Voicemail feature.