Metallizing Engineering Co. v. Kenyon Bearing and Auto Parts
153 F.2d 516 (2d Cir. 1946)
Meduna, (who worked for
Mettallizing) invented a new process for reconditioning metal parts.
Mettallizing began using the process to recondition the machine parts of
their customers, but kept the equipment and the process a secret.
They made a deliberate
effort to keep the process a trade secret.
More than a year later, they
applied for, and received a patent on the process. Some times after that,
Kenyon began using a similar process and Mettallizing sued for copyright
Kenyon argued that the
patent was invalid because the process was in public use for more than a year before being patented.
Patent law (now 35
U.S.C. §102(b)), says that you
can't patent something that was in public use, with the
consent and allowance of the inventor, for more than one year prior to
Mettallizing argued that the
process wasn't in public use, it
was a secret process and no one in the public could have figured out the
process just by looking at the reconditioned parts of Mettallizing's
That's known as a non-informing
The Trial Court found for
Mettallizing. Kenyon appealed.
The Trial Court found that
Mettallizing's use was not a public use, but a secret use,
and that did not invalidate the patent.
The Appellate Court reversed
and found the patent invalid.
The Appellate Court found
that just using the process commercially (as Mettallizing was doing)
counted as a public use, and that
invalidated the patent.
"That it is a
condition upon an inventor's right to a patent that he shall not exploit
his discovery competitively after it is ready for patenting; he must
content himself with either secrecy, or [a patent]."
The Court noted that if a third-party had invented the same process, but was working
in secret, then that would not invalidate an inventor's patent. §102(b)
is only applicable if the inventor himself is profiting off the invention (as what happened here).
Of course, the risk of just
keeping it a trade secret is that
some other inventor could independently come up with the idea and patent
it out from under you.
The Public Use Exception is important because the US has a "first
to invent" patent system. If the exception didn't exist, then a
person could invent something, sell it all over the place, and then only
apply for a patent once a competitor started copying it. Since no
competitors would copy the product knowing that the inventor could patent
it at any time, the inventor's monopoly would be indefinitely extended.