Perkins invented an
improvement to a water pump and got a patent on it. He sold the patent to
Lowell.
A little later, Baker invented
a similar improvement and got a patent on it, which he sold to Lewis.
Lowell sued Lewis for infringement.
Lewis argued that Perkins'
invention was not any better than what was already on the market.
Therefore it was not useful and
didn't deserve a patent.
It was 'different' and 'not
obvious' but it wasn't 'better'.
The Court found for Lewis.
The Court found that to
warrant a patent, the invention must be useful.
The Court defined useful as something that is capable of some
beneficial use, in contradistinction to what is pernicious, or
frivolous, or worthless. (aka moral utility)
It also has to actually
work. (aka practical utility)
The Court found that useful doesn't mean 'better', it just means
'different'.
"A new invention to
poison people, or to promote debauchery, or to facilitate private
assassination, is not a patentable invention. But if the invention steers
wide of these objections, whether it be more or less useful is a
circumstance very material to the interests of the patentee, but of no
importance to the public."
Basically, even if the pump
wasn't as good as other pumps on the market it is still patentable.
There is a public policy
reason for having people disclose inventions so that they can be used
as building blocks for potentially better inventions in the future.
Also, it is hard to judge
what is 'better'. An invention might be worse for most things, but
better for one specific thing.
This case is important because
it defined the usefulness
requirement.
The modern standard for usefulness is found in 35 U.S.C. §101.
See Juicy Whip, Inc. v.
Orange Bang, Inc. (185 F.3d 1364
(1999)).