Automotive Technologies International, Inc. (ATI) (plaintiff) was the assignee of a patent involving technology for a side-impact crash-sensing device for airbag deployment. The patent indicated that side-impact-sensing technology was a new field; the patent included five figures and a detailed explanation of a mechanical sensor assembly, which was described as the preferred type. The specification stated that electronic sensors could also be used, and a less detailed conceptual figure depicted an electronic sensor assembly. ATI brought an infringement suit against various automotive companies, including Delphi (defendant). Delphi moved for summary judgment, contending that the patent was invalid for lack of enablement because it provided an enabling disclosure only of mechanical side-impact sensors and not electronic sensors. ATI presented expert testimony that a person skilled in the art would know how to use existing electronic front-sensing technology to build an electronic side-impact sensor. The district court granted Delphi’s motion, finding that the patent did not enable the electronic sensor because making and using that type of sensor would require undue experimentation. ATI appealed.