After throwing the book at Web titans such as Facebook and YouTube Inc. , patent troll Pragmatus AV is directing its litigious gaze at several major US MSOs over claims that they are infringing on two patents linked to video-on-demand (VoD).

The suit (PDF), which could just as easily be extended to telcos or any other service provider doing VoD, names Cablevision Systems Corp. (NYSE: CVC), Comcast Corp. (Nasdaq: CMCSA, CMCSK), Cox Communications Inc. , Charter Communications Inc. , Time Warner Cable Inc. (NYSE: TWC) and Bright House Networks as defendants.

Pragmatus alleges they are violating two patents tied to how data is gathered and retrieved for VoD services: No. 5,636,139, which describes an "Information service control point which retrieves information as blocks of data," and No. 5,581,479, which describes another control point that uses different types of storage devices, retrieves information as blocks of data and uses a "trunk processor for transmitting information."

Both patents, filed in the 1990s, were originally assigned to Image Telecommunications Corp. of Westport, Conn., but, according to Paid Content, ended up in the hands of Virginia-based Pragmatus through a chain of transactions.

Pragmatus filed the complaint on Jan. 20 in the U.S. District Court for the District of Delaware. It's seeking unspecified damages.

This suit is just the latest to be filed against major MSOs over baseline technologies, and the last one didn't turn out well for the patent troll that tried it.

Rembrandt IP Management LLC tried to squeeze royalties and license fees from those same operators (save for Bright House) over the use of data-over-cable technology patents Rembrandt obtained via its acquisition of what was then Paradyne Networks. In Nov. 2009, a Delaware judge rejected those claims before a jury trial could get underway. (See Court Sides Against Cable Modem Patent Troll and MSOs Try to Brush Off Rembrandt Patents.)

— Jeff Baumgartner, Site Editor, Light Reading Cable