## Facts

- Automotive Technologies International, Inc. (ATI) owned U.S. Patent No. 5,231,253, directed to side-impact crash sensors for deploying occupant protection devices.
- ATI asserted claims describing a “velocity-type” side-impact sensor mounted on a vehicle door or side structure, including a movable mass and a threshold-triggered initiation mechanism.
- The specification described a detailed mechanical sensor embodiment with multiple figures.
- The specification also mentioned electronic sensor assemblies and included a high-level depiction, but provided little implementation detail compared to the mechanical disclosure.
- ATI sued multiple automobile manufacturers and suppliers alleging infringement by side-impact sensor systems.
- The district court construed the claims as broad enough to cover both mechanical and electronic side-impact sensors and granted summary judgment that claims 1–44 were invalid for lack of enablement under 35 U.S.C. § 112 ¶ 1.
- ATI appealed the invalidity ruling and related non-infringement rulings; certain defendants cross-appealed on non-infringement.

## Issues

1. Whether the patent’s specification enabled the full scope of the asserted claims—covering both mechanical and electronic side-impact sensors—without undue experimentation as required by 35 U.S.C. § 112 ¶ 1.
2. Whether summary judgment of invalidity for lack of enablement was proper on this record.
3. Whether infringement and non-infringement issues remained justiciable if the asserted claims were invalid.

## Decision

- The Federal Circuit affirmed summary judgment that the asserted claims were invalid for lack of enablement.
- The court held the claims, as construed, covered both mechanical and electronic sensors, but the specification did not enable electronic side-impact sensors.
- The court rejected ATI’s reliance on general knowledge in the art to supply missing teaching for electronic side-impact sensing in a developing and technically uncertain field.
- Because the asserted claims were invalid, the court treated the infringement appeal and cross-appeal as moot.

## Legal Principles

- Enablement requires the specification to teach a person of ordinary skill in the art to make and use the full scope of the claimed invention without undue experimentation.
- When claims cover multiple classes of embodiments, enablement must be commensurate with that breadth; enabling only a subset does not satisfy § 112 ¶ 1 for the broader claim scope.
- A patentee cannot cure a largely absent disclosure for an entire category of claimed embodiments by pointing to background knowledge, especially where the technology is not shown to be predictable and routine for the claimed application.
- Summary judgment of lack of enablement is appropriate when no reasonable factfinder could conclude the full claimed scope is enabled on the evidentiary record presented.

## Conclusion

The Federal Circuit affirmed invalidity because the patent claimed both mechanical and electronic side-impact sensors while providing enabling teaching only for the mechanical embodiment, leaving implementation of electronic side-impact sensing to undue experimentation; as a result, infringement disputes were moot.


Auto. Techs. Int’l, Inc. v. BMW of N. Am., Inc., 501 F.3d 1274 (Fed. Cir. 2007)