Space Systems/Loral v. Lockheed Martin (Fed. Cir. 2005)
By John Smith
Loral, the owner of U.S. patent 4,537,375 (the ‘375 patent), sued Lockheed for infringement of claim 1. The District Court ruled in favor of Lockheed, finding the claim invalid for violating the written description requirement of 35 U.S.C. § 112.
The ‘375 patent is directed to an improved method for maintaining the orientation and attitude of a satellite in space by a process known as station-keeping. After an initial thrust, the satellite re-checks its position, and often fires its thrusters again to better correct its position. Station-keeping thus uses the limited fuel supply on board a satellite and contributes to shortening the life of satellites. The ‘375 patent discloses a method directed to improving the efficiency of the corrective procedure.
Claim 1 of the ‘375 patent entails a multi-step procedure of thruster-firing, data storage, checking of position and correction of position, and minimization of error in correction of position. Essentially, the satellite fires its thrusters to correct its position, then checks its position and compares its current error in position to its previous error in position before firing its thrusters again. Lockheed argued that the patent was invalid, because the second step of claim 1 was not adequately described in the specification.
Defendant Lockheed’s expert, when asked at deposition where one would find the second step description, answered (over counsel objections) that the second step was depicted in Item 96 of Figure 2B. The court found this, along with the testimony of plaintiffs’ expert, established that the specification sufficiently described the claim.
Lockheed also argued that the second step of claim 1 was not inherent in the written description because the specification did not state that the second step was necessarily used in the satellite position correction procedure. On appeal, the Federal Circuit noted that the second step of the claim at issue in the procedure comes only (if at all) after thrusters are fired and actual position error and historical position error are compared. According to the Federal Circuit, this “does not diminish the descriptive content of the specification.”
The Federal Circuit reversed the finding of invalidity, and remanded back to the U.S. District Court for the Northern District of California for further proceedings.
John Smith is an attorney at MBHB LLP in Chicago. He earned both his JD and PhD (inorganic chemistry) from Vanderbilt University. He has co-authored numerous articles and served as a faculty member in the Chemistry Department of Lipscomb University in Nashville, Tennessee.
Notes:
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In his Case Alert, David Long of the Howrey firm correctly noted that this case should be “kept in mind by litigators taking or defending technical expert depositions on written description issues.”