Atlas Powder Co. v. E.I. DuPont de Nemours & Co.
750 F.2d 1569 (Fed. Cir. 1984)
Atlas had a patent on a type
of emulsion-based explosive that would explode even when wet.
Atlas' patent listed a whole
bunch of salts, fuels, and emulsifiers that could be used. It gave a few
examples of combinations that would work, but did not specify all the
combinations would work and all the ones that wouldn't.
A few years later, DuPont
began making their own formulation of an emulsion-based explosive. Atlas
sued for infringement.
DuPont argued that the claims in Atlas' patent were overbroad, and that the
patent didn't have enough disclosure to enable one of ordinary skill in the art to make the
claimed invention. Therefore the patent was invalid.
Basically, DuPont argued
that you'd still have to experiment with different combinations before
you figured out which would work. You couldn't just follow the
directions in Atlas' patent.
35 U.S.C. §112 ¶1 requires that a patent contain a description
that enables one skilled in the art to make and use the invention.
argument was that Atlas had invented a few different specific explosive
compounds, so they shouldn't be allowed to claim the entire concept of
emulsion-based explosives. Atlas should only get a patent on the
specific compounds they developed.
The Trial Court found for
Atlas. DuPont appealed.
The Trial Court found that
someone skilled in the art of explosive chemistry would know which
combinations would work and which wouldn't, so Atlas' description was
The Appellate Court affirmed.
The Appellate Court noted
that DuPont's chemists had little difficulty making suitable explosives
from the chemicals listed in Atlas' patent.
The Court found that Atlas
wasn't required to list every combination that would work and every
combination that would not. As long as they had some 'prophetic
examples' to guide people, that was enough to meet the enablement requirement.
There needs to be enough in
the patent application to "enable the full scope of the
Enablement is a significant restraint on claim breadth.
An inventor wants to draft claims that are broad enough to stop a
competitor from making a small change and getting around the patent, but
on the other hand, they can't have something that is so broad that it
covers variations that the inventor didn't actually develop.