The IT Law Wiki
The IT Law Wiki

Citation[]

Alpex Computer Corp. v. Nintendo Company Ltd., 102 F.3d 1214, 40 U.S.P.Q.2d (BNA) 1667 (Fed. Cir. 1996) (full-text).

Factual Background[]

This case involves a patent infringement suit brought by Alpex Computer Corporation (“Alpex”) against Nintendo Company Ltd. (“Nintendo”). Alpex, whose patent covers video game systems such as Atari, claimed Nintendo infringed Alpex’s patent by creating its own video game system — the Nintendo Entertainment System (NES).

Alpex was awarded the ‘555 patent in 1977. The ‘555 patent covered video game systems that operate using random access memory (RAM) that creates an entire image bit-by-bit before it is displayed on the screen. Unlike the Alpex systems, the NES video game system used what Nintendo called an “on-the-fly” technique. Instead of storing the display data for the entire screen in RAM, Nintendo’s system used eight shift registers, controlled by a picture processing unit (PPU), to alter a portion of the screen, up to 64 pixels, at a time. The NES PPU technology was faster and smoother than Alpex’s bit-mapping technology.

Trial Court Proceedings[]

In February 1986, Alpex filed a lawsuit against Nintendo, alleging infringement of one of its video game system patents (the ‘555 patent) relating to its video display system. Alpex argued that NES infringed claims 12 and 13 of the ‘555 patent. Specifically at issue was the portion of the claim which read "means for generating video signal." The trial court interpreted "means for generating a video signal" based on the structure defined in the ‘555 patent specification and drawings. Specifically, the jury was instructed that claims 12 and 13 corresponded to the structure in Figure 2 of the ‘555 patent, which consisted of ROM memory, a microprocessor, display RAM, display RAM control, and a television interface.

Nintendo argued that the trial judge approved an erroneous claim construction. Nintendo reasoned that its use of shifting registers for changing up to 64 pixels at a time was different from Alpex’s use of a RAM-based, bit-mapping system for changing one or all of the 32,000 pixels on a screen at a time. Nintendo also argued that Alpex was barred from claiming that Nintendo’s technology infringes on the ‘555 patent, because during prosecution, Alpex distinguished its technology from a prior art patent using shifting registers. Alpex argued that Nintendo waived its right to use prosecution history for prosecution history estoppel purposes.

Alpex was successful at trial, where the jury determined that Nintendo’s technology infringed Alpex’s ‘555 patent and awarded Alpex damages totaling $253,641,445. The trial court denied Nintendo’s post-trial motions and upheld the verdict. Nintendo appealed to the Federal Circuit.

Appellate Court Proceedings[]

Nintendo appealed the judgment as to validity, infringement, and damages, and Alpex appealed the amount of damages. The appellate court affirmed the validity of Alpex's patent but reversed the judgment as to infringement and damages because of a lack of substantial evidence to support a finding of infringement either literally or under the doctrine of equivalents. The court stated that Alpex had not established literal infringement because the testimony at trial was based on a functional and not a structural analysis. Further, there was no infringement under the doctrine of equivalents because the evidence did not establish that the claimed and accused devices operated in the same way or that the differences between them were unsubstantial. Alpex's appeal on the amount of damages was, therefore, moot.

The court found that both systems create game images, but that the images are created in distinguishably different ways through a different game processing structure. Second, the court found that the prosecution history was very relevant for determining the scope of the patent claims and prosecution history estoppel. The court decided that because Alpex explicitly rejected similarity to a previous system which processed images like the NES, the patent scope was narrowed so that the NES was not included in that scope. Thus, the Federal Circuit reversed the trial court’s judgment as to infringement and damages.