Lack of Enablement – A Stronger Tool for Invalidity

One of the requirements of a valid patent is enablement. As set forth in 35 U.S.C. section 112, paragraph 1, a patent’s specification must contain “a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art to which it pertains, or with which it is most nearly connected, to make and use the same.” The Court of Appeals for the Federal Circuit has explained that the enablement requirement is met “when one skilled in the art, after reading the specification, could practice the claimed invention without undue experimentation.” AK Steel Corp. v. Sollac, 344 F.3d. 1234, 1244 (Fed. Cir. 2003). Although anticipation or obviousness based on the prior art is a more frequently asserted basis for invalidating a patent in patent infringement litigation, the Federal Circuit’s decision in Sitrick v. Dreamworks, LLC, 516 F.3d. 993 (Feb. 1, 2008) suggests that lack of enablement may be becoming a far more powerful tool.

In Sitrick, the plaintiff owned two patents that covered technology that allows integration of a user’s audio signals or visual image into a preexisting video game or movie. The specifications of the two patents described the invention as it was used in video games, but the claims covered both video games and movies. Dreamworks produced DVDs that included a product that permitted users to add their own voice to movies. Sitrick sued Dreamworks for infringement of both patents.

During claim construction, Dreamworks argued that the claims should be narrowed to cover only video games. The plaintiff opposed that construction, and the court construed the claims as plaintiff requested, to cover both video games and movies.

Dreamworks moved for summary judgment, including for invalidity for lack of enablement. The District Court for the Central District of California granted the motion, finding all of the challenged claims invalid for lack of enablement with respect to movies.

The Court of Appeals affirmed. The court explained that in order to satisfy the enablement requirement, “the full scope of the claimed invention must be enabled.” Sitrick, supra, at 999. The court explained its rationale:

“Enabling the full scope of each claim is ‘part of the quid pro quo of the patent bargain.’ AK Steel, supra, 344 F.3d. at 1244. A patentee who chooses broad claim language must make sure the broad claims are fully enabled. ‘The scope of the claims must be less than or equal to the scope of the enablement’ to ‘ensure that the public knowledge is enriched by the specification to a degree at least commensurate with the scope of the claims.’[citation omitted].”

The court found that because the district court had construed the claims to cover both video games and movies (as the plaintiff had argued), the patents had to enable both embodiments. The specifications described the detailed steps required for integrating a visual image into a video game, but these steps were not usable for the same process in movies and the patents did not describe how to integrate an image into a movie.

The court stated that it was irrelevant if the patents were enabled for video games – the enablement requirement was not met unless the patents were enabled for both embodiments of the invention, video games and movies. Sitrick, supra, at 1000.

The court held that Dreamworks’ evidence, consisting of the specifications of the two patents and expert testimony, was clear and convincing evidence of lack of enablement. The patents did not teach how to use, in movies, the technology described for using the invention in video games. In addition, defendants’ experts testified that a person skilled in the art could not use the specifications to utilize the invention in movies because video games and movies differed in many respects.

In an earlier case, Automotive Technologies International, Inc. v. BMW of North America, Inc. 501 F.3d. 1274 (Fed. Cir. 2007), the court reached the same conclusion. In that case, the plaintiff’s patent covered side impact sensors used in airbags. The patent’s specification described mechanical sensors in detail, but also mentioned electronic sensors, and the claims covered both types of sensors. The district court granted a defendant’s motion for summary judgment on invalidity on the grounds that the full scope of the claims covered electronic sensors as well as mechanical sensors, but the specification did not teach a person skilled in the art how to make and use the invention with an electronic sensor.

On appeal, the plaintiff argued that because one embodiment, mechanical sensors, was enabled, the claims were enabled. The Court of Appeals held to the contrary, at 1285:

“…[T]he claim construction of the relevant claim limitation resulted in the scope of the claims including both mechanical and electronic side impact sensors. Disclosure of only mechanical side impact sensors does not permit one skilled in the art to make and use the invention as broadly as it was claimed, which includes electronic side impact sensors. Electronic side impact sensors are not just another known species of a genus consisting of sensors, but are a distinctly different sensor compared with the well-enabled mechanical side impact sensor that is fully discussed in the specification. Thus, in order to fulfill the enablement requirement, the specification must enable the full scope of the claims that includes both electronic and mechanical side impact sensors, which the specification fails to do.”

The plaintiff also argued that a person skilled in the art would be able to figure out how to use an electronic sensor in the invention. The court disagreed. “‘It is the specification, not the knowledge of one skilled in the art, that must supply the novel aspects of an invention in order to constitute adequate enablement.’ Although the knowledge of one skilled in the art is indeed relevant, the novel aspect of an invention must be enabled in the patent.” Id. at 1283. The court explained that “when there is no disclosure of any specific starting material or of any of the conditions under which a process can be carried out, undue experimentation is required.” Id. at 1284.

Thus in both Strick and Automotive Technologies, the plaintiffs had sought and obtained a broad claim construction, but had lost the case on summary judgment due to their failure to show that the scope of the claims was enabled.

Some commentators have questioned whether the Federal Circuit is setting the enablement standard too high. That remains to be seen. At this point, however, it is clear that patent litigation plaintiffs should carefully consider the specification in seeking a broad claim construction, and defendants should scrutinize the broad claims to see if invalidity based on lack of enablement can be asserted.