Lockheed Martin Corp. v. Space Systems/Loral, Inc.

• Decision Date: 24 March 2003
• Docket Number: No. 00-1310.,00-1310.
• Citation: 324 F.3d 1308
• Parties: LOCKHEED MARTIN CORPORATION, Plaintiff-Appellant, v. SPACE SYSTEMS/LORAL, INC., Defendant-Appellee.
• Court: U.S. Court of Appeals — Federal Circuit

324 F.3d 1308

LOCKHEED MARTIN CORPORATION, Plaintiff-Appellant, v. SPACE SYSTEMS/LORAL, INC., Defendant-Appellee.

No. 00-1310.

United States Court of Appeals, Federal Circuit.

March 24, 2003.

Edward V. Filardi, Skadden, Arps, Slate, Meagher & Flom, LLP, of New York, NY, for plaintiff appellant. With him on the brief were Robert B. Smith, of New York; and David W. Hansen, of Palo Alto, California.

James H. Wallace, Jr., Wiley, Rein and Fielding LLP, of Washington, DC, for defendant-appellee. With him on the brief were Gregory R. Lyons, John B. Wyss and Scott E. Bain.

Before SCHALL, Circuit Judge, FRIEDMAN, Senior Circuit Judge, and GAJARSA, Circuit Judge.

DECISION

GAJARSA, Circuit Judge.

This case has been remanded to this court by the United States Supreme Court for further consideration in light of Festo Corp. v. Shoketsu Kinzoku Kogyo Kabushiki, Co., 535 U.S. 722, 122 S.Ct. 1831, 152 L.Ed.2d 944 (2002). The Supreme Court granted a petition for certiorari following our earlier decision in this case, vacated our decision, and remanded following its decision in Festo. Lockheed Martin Corp. v. Space Sys./Loral, Inc., 249 F.3d 1314, 58 USPQ2d 1671 (Fed.Cir.2001), vacated, 535 U.S. 1109, 122 S.Ct. 2349, 153 L.Ed.2d 152 (2002). We have carefully reviewed the Festo decision and have considered its impact on the various issues raised by the parties, especially with regard to the prosecution history estoppel effect as may be amended by Festo. However, other grounds were also briefed and argued by the parties. We now review and consider those other grounds in order to avoid further delay in the resolution of this long, complex, and protracted litigation. Based upon the alternative grounds, we affirm the decision of the United States District Court for the Northern District of California ("district court") in this case on a basis that does not implicate the Supreme Court's decision in Festo.

I. BACKGROUND

In the prior appeal, Lockheed Martin Corporation ("Lockheed") challenged the district court's grant of summary judgment of noninfringement on various grounds. See Lockheed, 249 F.3d at 1322-26, 58 USPQ2d at 1676-79. We affirmed on the single ground that under our prior decision in Festo Corp. v. Shoketsu Kinzoku Kogyo Kabushiki Co., 234 F.3d 558, 56 USPQ2d 1865 (Fed.Cir.2000) (en banc), vacated, 535 U.S. 722, 122 S.Ct. 1831, 152 L.Ed.2d 944, "`prosecution history estoppel [bars] the application of the doctrine of equivalents' to limitation [b]," the critical claim limitation at issue in the case. Lockheed, 249 F.3d at 1327, 58 USPQ2d at 1680 (citing Festo, 234 F.3d at 586, 56 USPQ2d at 1886).

The Supreme Court reversed our Festo decision, holding that we had misinterpreted and misapplied the doctrine of equivalents. Festo, 535 U.S. 722, 122 S.Ct. 1831, 152 L.Ed.2d 944. It then entered the following order on Lockheed's petition for a writ of certiorari seeking review of our decision in the prior appeal:

Petition for writ of certiorari granted. Judgment vacated, and case remanded to the United States Court of Appeals for the Federal Circuit for further consideration in light of Festo Corp. v. Shoketsu Kinzoku Kogyo Kabushiki Co., 535 U.S. 722, 122 S.Ct. 1831, 152 L.Ed.2d 944 (2002).

535 U.S. 1109, 122 S.Ct. 2349, 153 L.Ed.2d 152 (2002).

On the same day, the Court entered identical orders in eight other cases coming from this court on petitions for writ of certiorari. See 535 U.S. 1108-1109, 122 S.Ct. 2322-24 (2002).

The Supreme Court thus followed its routine practice of summarily "vacat[ing] the judgment below, and remand[ing] the case to the lower court for reconsideration in light of an intervening Supreme Court ruling." Robert L. Stern et al., Supreme Court Practice 317 (8th ed.2002) (footnote omitted).

We do not interpret the Supreme Court's order in this case as requiring us to address the Festo issue or as precluding us from deciding the case on some other ground. Because the Court vacated our prior judgment affirming the district court's order granting summary judgment, the case on remand stands in the same posture as it did in the earlier appeal before our decision there. We think that all the Supreme Court intended was that, if we again considered the prosecution history estoppel point, we should do so in light of the Court's elucidation of that doctrine in its Festo opinion. There is no reason to believe, however, that the Supreme Court intended to require us on remand to limit our analysis to the theory we previously had followed. Indeed, our disposition of this appeal on grounds other than prosecution history estoppel literally complies with the Supreme Court's order in the sense that, "in light of Festo," we have "further consider[ed]" the case and concluded that the judgment of the district court should be affirmed on another ground.

A. Introduction

Lockheed is the assignee of U.S. Patent No. 4,084,772 ("the '772 patent"), which discloses an apparatus and method for steering a satellite. In 1995, Lockheed's predecessor, Martin Marietta Corporation, brought this patent infringement action against Space Systems/Loral, Inc. ("SSL"), alleging that certain SSL satellites infringe the '772 patent. The '772 patent, entitled "Roll/Yaw Body Steering for Momentum Biased Spacecraft," claims a structure and method for reducing the pointing errors of a satellite that has entered into an inclined orbit by varying the speed of the satellite's transverse momentum wheel in a sinusoidal manner.

A communications satellite typically orbits the earth in a geosynchronous equatorial orbit, circling the earth once every twenty-four hours in the equatorial plane. A geosynchronous orbit in the equatorial plane allows a satellite to maintain the same position relative to fixed points on the earth's surface, and is often referred to as "geostationary." A satellite in geostationary orbit, when viewed from the ground, appears to remain stationary in the sky. Therefore, a geostationary orbit enables a communications satellite to maintain a constant relationship with transmitters on earth. In addition to preserving a geosynchronous equatorial orbit, a communications satellite must also maintain a proper "attitude," or pointing direction, so that its antennae remain pointed at the desired target on the earth.

While in orbit, however, a satellite is subject to various destabilizing forces such as the gravitational effects of the sun and the moon. Such forces may cause a satellite to drift out of its equatorial orbit, into an "inclined" north-south orbit. A satellite in an inclined orbit may still orbit the earth in a geosynchronous manner (once every twenty-four hours), but may no longer appear stationary in the sky to an earthbound observer. The following diagram, Figure 2 of the '772 patent specification, depicts an inclined orbit relative to an equatorial orbit:

NOTE: OPINION CONTAINING TABLE OR OTHER DATA THAT IS NOT VIEWABLE

Therefore, in an inclined orbit, the antennae of a communications satellite point north of the equator for half of the orbit and south of the equator for half of the orbit. Unless the satellite corrects for solar and lunar gravitational effects, the orbit of a geosynchronous satellite acquires an inclination at the rate of about 0.8 degrees annually.

The '772 patent discloses a system for allowing a communications satellite to continue to operate effectively after entering an inclined orbit. It does so by changing the attitude, or pointing direction, of the satellite when the satellite is north and south of the equator. The method described by the '772 patent rotates the satellite so that its antennae point north or south, and remain pointed at the same earth target over the course of twenty-four hours.

The attitude of satellites is described in terms of movement and rotation about three axes. The "pitch" axis lies in a north-south direction, the "roll" axis points in the direction of satellite orbital movement, and the "yaw" axis points to the center of the earth. In an inclined orbit, roll pointing error occurs when a satellite is north or south of the equator. There is no roll pointing error when a satellite is above the equator twice each orbit (depicted above in Figure 2 at points B and D). Conversely, yaw pointing error is greatest when a satellite crosses the equator. There is no yaw pointing error when a satellite is furthest north or south of the equator (depicted above in Figure 2 at points A and C).

The structure and method described by the '772 patent rotates a satellite around its roll axis such that its antennae point to the south when the satellite is north of the equator, and point to the north when the satellite is south of the equator. In this manner, even though a satellite is moving north and south during its orbit, it remains pointed at the same earth target, and behaves as if it were still in geostationary orbit.

B. The '772 Patent Technology

Many communication satellites employ at least one "momentum" or "reaction" wheel centered on the pitch axis of a satellite ("pitch wheel") powered by an electric motor. A spinning momentum wheel creates angular momentum, or "stiffness," and opposes any satellite rotation about the roll or yaw axis. In other words, the spinning pitch wheel acts like a gyroscope, resists external forces, and keeps the pitch axis pointed in a north-south direction.

In addition to this resistance effect, momentum wheels also cause a satellite to rotate around its axes by taking advantage of the physical law of conservation of angular momentum. When a momentum wheel increases speed in one direction, it causes the entire satellite to spin in the opposite direction along the same axis in order to conserve angular momentum. Thus, through careful control of momentum wheels centered on different axes, a proper satellite attitude can be maintained.

As discussed above, the invention described by the '772 patent is a structure and method for spinning...