General Electric Sues Mitsubishi Over Wind Energy Patents

2.4 MW wind turbine MWT92/2.4

On February 11, 2010, General Electric (NYSE: GE) launched a patent infringement lawsuit in the United States Federal District Court for the Northern District of Texas. Caught in the cross-hairs is Mitsubishi Heavy Industries, Ltd. (TYO:7011), Mitsubishi Heavy Industries America, Inc. and Mitsubishi Power Systems Americas, Inc. (hereinafter “Mitsubishi). The complaint alleges that GE engages in the development, manufacture, and distribution of variable speed wind turbines and components, and that GE is the assignee and owns all right, title and interest to US Patent No. 6,879,055 and US Patent No. 7,629,705, which are being infringed by Mitsubishi. A jury trial has been demanded in this Green Tech patent dispute; the type of dispute we are all but certain to see increasingly more often as the alternative energy market continues to mature and become more economically relevant.

According to the complaint filed by GE, provided courtesy of The Docket Report, which is not terribly long and largely, although not completely, devoid of much useful information, Mitsubishi has either directly, indirectly, contributorily, and/or by inducement infringed, either literally or under the doctrine of equivalents, the ‘055 patent and the ‘705 patent. The relevant statements about infringement, of some kind, are asserted based upon “information and belief.” So GE is not exactly sure what kind of infringement there is, but is pretty sure there is some kind of infringement. Not typically the level of detail that I would consider to be appropriate for a complaint, although this type of complaint is getting more and more common no doubt. It would be nice to at least have some discussion of the claims, but in the litigious patent world where so many lawsuits are filed for strategic purposes and to create leverage that is asking a lot I suppose, particularly if the District Courts will let you get away with minimal disclosure in a complaint.

Now, to be perfectly fair, this complaint is not completely devoid of information. The complaint provides by way of example an illustration of an allegedly infringing product, so at least the defendants will have something to work with out of the box. GE asserts that the Mitsubishi 2.4MW wind turbine is an example of an infringing product. The 2.4 MW wind turbine is a large-size wind turbine with a 2.4 megawatt rated output. According to the Mitsubishi website, the MWT92/2.4 and MWT95/2.4 (versions of the 2.4MW wind turbine) “are strategically targeted at the global market for large-scale wind turbine generators. MHI developed the MWT92/2.4 proprietarily and, since January 2006, has verified its performance and reliability through testing…” As of April 2007, Mitsubishi had received some 287 US orders for the 2.4 MW wind turbine, with the first orders for the unit coming from PPM Energy, Inc., a US electricity provider, who ordered 42 units.

According to the ‘055 patent, which issued on April 12, 2005 from an application filed April 19, 2002, the invention involves a base frame for the arrangement of a drive train on the tower of a wind power plant. The purpose of the invention is to create a base frame that can be more easily transported and assembled, while still having sufficient stability. The invention achieves this purpose by having the connection point extend along an essentially horizontal cross-section, which has a larger dimension in the direction of the rotor axis than in the direction perpendicular to that. By the two-part construction of the base frame, a division of the total mass and the total dimensions into two partial systems is achieved, each of which can be transported more easily to the construction site and lifted to the tower.

According to the ‘705 patent, which issued on December 8, 2009 from an application filed October 20, 2006, typical wind turbine generator include a turbine that has a rotor that includes a rotatable hub assembly having multiple blades. The blades transform mechanical wind energy into a mechanical rotational torque that drives one or more generators via the rotor. Under certain circumstances, grid voltage fluctuations may be experienced, including low voltage transients with voltage fluctuations that approach zero volts. Generally, the power converters and the generator are susceptible to grid voltage fluctuations, which means that voltage fluctuations may be detrimental to continuous operation of the wind turbine generator. The invention of the ‘705 patent provides a method for coupling the electrical machine to an electric power system so the power system transmits at least one phase of electric power to and from the electrical machine. The method further includes configuring the electrical machine so it will remain electrically connected to the electric power system during and subsequent to a voltage amplitude of the electric power system operating outside of a predetermined range. There is also a control system associated with the method, which is also covered by claims in the ‘705 patent.

According to the prayer for relief contained within the complaint, GE is seeking fairly standard relief, including a permanent injunction upon Mitsubishi being adjudged to infringe the ‘055 and ‘705 patents, an accounting and damages appropriate to compensate GE pursuant to 35 USC 284, the assessment of pre-judgment and post-judgment interest in the event of prevailing, and attorneys’ fees if the Court determines the case to be an “exceptional case” within the meaning of 35 USC 285.  What seems to be missing, however, is any request for a preliminary injunction.  Perhaps in time, after service is affected, a request for a preliminary injunction will arrive.

While I am not sure I can articulate exactly why, in reading the complaint it seems to me that this is not likely a declaration of patent war or jihad, but rather to create leverage.  Perhaps it is the relative politeness of the complaint.  Patent litigators can go for the jugular like none other, and GE’s attorneys – Weil, Gotshal & Manges – are hardly novices in the art of patent litigation.  Time tells all things, and soon enough we will see how Mitsubishi responds.  Let the posturing begin!


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Join the Discussion

5 comments so far.

  • [Avatar for wind generator]
    wind generator
    September 11, 2010 01:01 pm

    This post was mentioned on Twitter by ipwatchdog: General Electric Sues Mitsubishi Over Wind Energy Patents. GE asserts the 2.4MW wind turbine is an infringing product.
    According to the Wall Street Journal GE has 148 patents relating to wind energy. I would have thought they had more, so maybe there are other patents likely to come in the future that will be infringed.

  • [Avatar for Jessica Taylor]
    Jessica Taylor
    April 30, 2010 10:21 pm

    Wind power is a good source of electricity but it also takes up lots of space just like solar power plants.-`~

  • [Avatar for EG]
    February 15, 2010 10:45 am


    My take would be GE isn’t interested in a “total patent war” with Mitsubishi. Given that these are two large corporations and that Mitsubishi is a well-established Japanese competitor, an “aggressive” complaint would likely be considered bad form, especially if GE is primarily interested in settling this dispute without going “nuclear.” We also don’t know if GE might be interested in cross-licensing some technology that Mitsubishi has (possibly in Japan). Just some thougths off the top of my head.

  • [Avatar for Gene Quinn]
    Gene Quinn
    February 12, 2010 06:22 pm


    That is very curious indeed. Perhaps these are viewed as core patents, or perhaps they are the only ones where infringement can be alleged in good faith without discovery. Who knows?

    According to the Wall Street Journal GE has 148 patents relating to wind energy. I would have thought they had more, so maybe there are other patents likely to come in the future that will be infringed.

    What is your take on how straight forward and relatively polite the complaint seems? No grand standing and even a polite prayer for relief.


  • [Avatar for EG]
    February 12, 2010 05:13 pm


    Interesting pair of patents that GE is suing Mitsubishi on. It’s odd that each of these patents cover distinct aspects of wind turbine technology (the hub for the blades and a method for managing the energy conversion from the wind turbine). I know GE has many patents on wind turbines. I wonder why only this pair was picked.

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