California-based firm Target Technology has filed a lawsuit against three Sony companies - including SCEA - claiming that the Blu-ray format infringes on a patent it has held since March 2006.
According to IPlaw360.com, Target alleges that Blu-ray discs "embody" a silver-based alloy thin film it invented to be used on optical discs.
The lawsuit, which was filed earlier this month, names Sony Computer Entertainment America, Sony Pictures and Sony DADC US.
Target is seeking a jury trial, damages and a permanent injunction which would stop Sony from allegedly infringing on its patent rights in the future.
According to IPlaw360, Target has filed two other federal court lawsuits over a different patent for optical disc alloys, accusing manufacturer Williams Advanced Materials and its customers of infringing ten patents.
Target claims that company founder Han Nee developed the reflective silver alloy material which is used as a component of most DVDs produced today.
Sony has so far declined to comment on the lawsuit.