US digital television specialist OpenTV, a subsidiary of Switzerland-based Kudelski, has filed a patent infringement lawsuit against Netflix, alleging that it had infringed seven of its US patents.

The lawsuit was filed in the US District Court in Delaware, and OpenTV is represented by Kirkland & Ellis.

According to Reuters, the lawsuit covers aspects of over-the-top TV technology (OTT), including: the use of viewer information to make recommendations; digital rights management; and video playback.

Reuters quoted Kudelski as saying "Companies like Netflix have, in essence, stood on the shoulders of giants, largely focusing their R&D efforts on aggregating these previously patented technologies and using them to provide a rich customer experience."

The lawsuit says OpenTV first contacted Netflix CEO Reed Hastings through a letter in December 2011. The letter outlined patent holdings and informed Hastings that the patents may apply to Netflix services but the company did not reply to the letter.

Founded in 1994, OpenTV provides advanced digital television solutions and was acquired by Kudelski in 2010.