EB: My Example for Doctrine of Equivalents
Sage Products, Inc. v. Devon Industries, Inc., 126 F. 3d 1420 - Court of Appeals, Federal Circuit 1997
Sage sues Devon for infringement of several patents relating to containers for disposing of hazardous medical waste (needles etc.). Devon counter-sues for infringement of one of its similar patents.
The district court held (on summary judgement) that there was no infringement by either party literally or equivalently. The appellate court affirms.
Part 1: Sage sues Devon for infringement of their container which claims an elongated slot "at the top" of the apparatus for which to deposit waste, and a "barrier over the slot" to prevent contamination.
- Devon's patent involved a type of elongated slot that was embedded within the container and a hinged element at the opening.
- Court ruled no literal infringement because the Devon patent did not include the "at the top" and "over" features of the Sage claim.
- Court ruled no equivalent infringement because even though the devices perform the same function the doctrine of equivalents does not grant the ability to negate the "at the top" and "over" limitations of the patent claims. Furthermore, the hinged element did not "substantially constrict access" to the container, and the slot was not "substantially at the top" of the container.
- If the doctrine of equivalents could negate patent claims than it would reduce patents claims to "functional abstracts" devoid of meaningful structure limitations for the public to reference.
Part 2: Sage sues Devon for infringement of its patent on a needle disposal container with a movable "closure means."
- Sage's lid was pivotable and selectively closeable by gripping the handle of the container. Devon's patent only had a lid that locked simply in place - there was no "control access."
- Court ruled that if claims specify a function and recite its importance the patentee cannot later argue that an invention without the function is infringing.
Part 3: Devon sues Sage for infringement of another type of waste container. The decision is not particularly relevant for our purposes.