Alexander Milburn Co. v. Davis-Bournonville Co.
270 U.S. 390 (1926)
Clifford invented a new type
of welding torch. He filed a patent application that completely described
the new torch, but in the claims
section, it didn't claim one specific improvement that had been described
in the description section.
Clifford's patent disclosed but didn't claim.
A little later, Whitford
independently came up with the same improvement. He filed a patent on the
improvement. Both Clifford and Whitford's patents were granted.
Davis-Bournonvilleowned Whitford's patent. They sued Milburn
(who was manufacturing a similar welding torch) for infringement.
Milburn countersued and
claimed that Whitford's patent was invalid.
Milburn argued that Clifford
invented the improvement first, so Whitford could not rightfully patent
The Trial Court found for Davis-Bournonville.
The Trial Court found that Clifford
might have added this claim to his
application, but he didn't, so he was not a prior inventor.
The Court found that (under
what is now 35 U.S.C. §102(g)) if
a second filer can show conception and reduction to
practice before the first filer
filed, then the second filer gets the patent. The Court found without a claim, the thing described is not reduced
The Appellate Court affirmed.
The US Supreme Court reversed.
The US Supreme Court found
that Clifford's description in his patent application satisfied the
requirement of reduction to practice,
even though Clifford had not made a claim on that specific improvement.
" A description that
would bar a patent if printed in a periodical or in an issued patent is
equally effective in an application so far as reduction to practice
The Court found that since
there was evidence Clifford had both conceived of and reduced to practice prior to Whitford's filing, Whitford's patent
The Court based their
reasoning on the idea that if the USPTO was 'divinely efficient' they
would grant patents on the same day that they were filed. Any delay
between filing and grant is the fault of the inefficient USPTO and
inventors should not be punished for that.
This was an unusual ruling
because it basically said that patent applications (which are generally
secret until the patent is issued) count as the prior art despite the fact that they aren't available in
the public domain.
On the other hand, had this
case gone the other way, Clifford would have been infringing on
Whitford's patent. Would that be fair to Clifford?
The ruling in this case was
later codified in 35 U.S.C. §102(e).
Disclosures that are not
claimed in a patent application are still considered to be in the public
domain and are prior art.