Mobile communications firm NTP has filed patent infringement cases against Apple, Google and Microsoft.
NTP won $612m from BlackBerry maker Research in Motion in a similar patent infringement lawsuit.
NTP said it is also planning to sue Motorola, HTC and LG over patents covering wireless e-mail transmissions, according to the Financial Times.
The cases were filed in a US federal court in Virginia where NTP was victorious over RIM in a jury trial four years ago.
The new cases do not seek a specific amount of damages but settlement negotiator for NTP, Ron Epstein, said the judge in the RIM case had decreed NTP was entitled to royalties of 5.7% of the revenue from the hardware at issue.
