By Dennis Crouch
In 1931, the United States Supreme Court decided a landmark case on the patentability of inventions, De Forest Radio Co. v. General Electric Co., 283 U.S. 664 (1931), amended, 284 U.S. 571 (1931). The case involved a patent infringement suit over an improved vacuum tube used in radio communications. While the case predated the codification of the nonobviousness requirement in 35 U.S.C. § 103 as part of the Patent Act of 1952, it nonetheless applied a similar requirement for “invention.”
I wanted to review the case because it is one relied upon in the recent Vanda v. Teva petition, with the patentee arguing that the court’s standard from 1931 has been relaxed by the Federal Circuit’s “reasonable expectation of success” standard. The decision also provides an interesting case study in the way that the court seems to blend considerations of obviousness and patent eligibility under the umbrella of the “invention” requirement, in a way that may seem foreign to contemporary patent law.
Background
The patent at issue, U.S. Patent No. 1,558,436 granted to Irving Langmuir in 1925 and owned by General Electric, claimed an improved vacuum tube for use in radio communications. Before the advent of transistors, vacuum tubes were widely used as amplifiers and oscillators in radio, television, radar, and computer systems. Langmuir’s key insight was that by evacuating the tube to a very high vacuum, on the order of a few hundredths of a micron of mercury pressure (about 1/1000 of normal atmospheric pressure), he could achieve a stable current flow unaffected by residual gas ionization in the tube. This was an improvement over prior art vacuum tubes which used weaker vacuums.
The Delaware federal court initially dismissed GE’s infringement complaint, holding Langmuir’s patent invalid for lack of invention and anticipation by prior use. On appeal, the Third Circuit Court of Appeals at first affirmed, but then on rehearing reversed, holding the patent valid and infringed. De Forest Radio petitioned the Supreme Court for certiorari, which was granted.
The Supreme Court’s Analysis: Blending Obviousness and Eligibility
In a unanimous opinion by Justice Stone, the Supreme Court reversed the Third Circuit and held Langmuir’s patent invalid for lack of invention. The Court’s analysis is notable for the way it seems to mix considerations of what we would now call obviousness under 35 U.S.C. § 103 and patent eligibility under 35 U.S.C. § 101, all under the general rubric of the “invention” requirement.
The Court began by surveying the prior art, which showed that the scientific principles and methods for creating high vacuums in tubes were already well-known. The Court found that the art already recognized that residual gas ionization caused instability and that this effect could be mitigated by increasing the vacuum. The key question, according to the Court, was whether Langmuir’s application of these principles to make an improved vacuum tube was an inventive act or merely the work of routine skill:
The narrow question is thus presented whether, with the knowledge disclosed in these publications, invention was involved in the production of the tube, that is to say, whether the production of the tube of the patent, with the aid of the available scientific knowledge that the effect of ionization could be removed by increasing the vacuum in an electric discharge device, involved the inventive faculty or was but the expected skill of the art.
This portion of the opinion sounds very much like the modern obviousness inquiry, asking whether the claimed invention would have been apparent to a skilled artisan in light of the prior art. The Court concluded that “it did not need the genius of the inventor” to recognize the benefits of a higher vacuum once the underlying scientific relationship was known. Of course, we know that under post-52 law, “genius” is not required so long as the result would not have been obvious to a person skilled in the art.
At the same time, the Court also emphasized that “it is method and device which may be patented and not the scientific explanation of their operation.” citing the key eligibility case of Le Roy v. Tatham, 14 How. 156 (1852). This concern with distinguishing patentable applications from unpatentable scientific principles sounds more like the modern eligibility analysis under § 101. In their highly regarded textbook on Patentability and Validity, Rivise and Caesar identified De Forest Radio as one of three 20th century “abstract principle” cases as of 1936. (Note I did not go back and read this old book, but rather found the reference in Jeffrey A. Lefstin, Inventive Application: A History, 67 Fla. L. Rev. 565, 648 (2015). This mixture of obviousness and eligibility continued in the Supreme Court’s 1948 Funk Brothers case.
Objective Indicia and Prior Use
De Forest Radio also considered evidence of the invention’s impact and success, in a manner resembling the modern analysis of objective indicia of nonobviousness. However, the Court found this evidence unpersuasive, stating that the invention’s utility was not “indicative of anything more than the natural development of an art which has passed from infancy to its present maturity since Langmuir filed his application.” As Professor Risch has observed, the Court here “consider[ed] ‘present utility’ as a secondary factor to show nonobviousness,” even if it ultimately gave this factor little weight. Michael Risch, A Surprisingly Useful Requirement, 19 Geo. Mason L. Rev. 57, 111 (2011).
In addition to finding Langmuir’s claimed invention obvious, the Court also agreed with the district court that it was anticipated by De Forest’s own prior use of high-vacuum tubes. Crucially, the Court held that De Forest’s incomplete understanding of the scientific principles involved did not negate this prior use:
Whether De Forest knew the scientific explanation of it is unimportant, since he did know and use the device and employ the methods, which produced the desired results, and which are the device and methods of the patent.
This holding reaffirmed the principle that prior use by a third party will negate patentability even if the earlier user did not appreciate the invention’s benefits or even its underlying mechanism.
Today
The petitioner in Vanda cites De Forest Radio as applying a lower standard for inventiveness than the Federal Circuit’s current “reasonable expectation of success” test for obviousness. The argument is that the Supreme Court in De Forest Radio only asked whether the invention would be “immediately recognized” by a skilled artisan, not whether they would have had a reasonable expectation of success in making it. This distinction is urged as a reason to dial back the obviousness requirement and allow the issuance and enforcement of more patents. Whether the Supreme Court will find these arguments persuasive remains to be seen.
“The Court’s analysis is notable for the way it seems to mix considerations of what we would now call obviousness under 35 U.S.C. § 103 and patent eligibility under 35 U.S.C. § 101, all under the general rubric of the ‘invention’ requirement.”
Whew! Thank goodness neither today’s SCOTUS nor CAFC would ever conduct such improper 103/101 mixing.
Thank goodness.
“In addition to finding Langmuir’s claimed invention obvious, the Court also agreed with the district court that it was anticipated by De Forest’s own prior use of high-vacuum tubes. Crucially, the Court held that De Forest’s incomplete understanding of the scientific principles involved did not negate this prior use:
Whether De Forest knew the scientific explanation of it is unimportant, since he did know and use the device and employ the methods, which produced the desired results, and which are the device and methods of the patent.
This holding reaffirmed the principle that prior use by a third party will negate patentability even if the earlier user did not appreciate the invention’s benefits or even its underlying mechanism.'”
But they did not find it obvious. In addition to finding it anticipated, they found it was not the result of inventive faculty, but of the expected skill in the art. This sounds more like “reasonable expectation of success” to me. But, I have not read the case just the excerpts here.
The improvement upon the prior art was the removal of residual gas that was present in the DeForest Audion, which had the same physical structure but used a partial vacuum.
DeForest had erroneously believed that gaseous ions were necessary for as a charge carrier. Langmuir determined that emission in a vacuum tube operated on free electron emission, so that residual gas was not necessary (and was in fact deleterious to longevity of the tube).
The Court said that even such a slight change as a few microns’ difference in vacuum could qualify as “invention” – that is, could be non-obvious – if free electron emission was not known prior to Langmuir’s invention. However, the Court found that the phenomenon of free electron emission had been previously described, and the removal of residual gas in the tube was therefore obvious.
No – they could not have ruled that way – and if they had, they would not have been applying the actual law.
That this old case took a costly 3d Cir. appeal and its reconsideration and then a Sup. Ct. decision to get such an obvious obviousness decision on prior art is why we got the CAFC taking cases away from local circuit courts, and then IPRs.
As ever, everything changes and yet everything stays the same. Even when it comes to the obviousness enquiries in, respectively, 1931 and 2024.
Like it or not, anon, in the real world,”obvious” and “inventive” are, and have always been, antonyms of each other.
The key question is today, and has always been, NOT what the POSA at the time COULD have done but rather, WOULD the POSA at the time, in the course of following the “natural development” of the art, have done what the claim recites.
Obvious, from the Latin for “lying in the road”.
Antonyms….
De Forest: asks whether there was public information “confirming that the desired result would be obtained.” Confirming to whom? The public, the court, the inventor?
Current 103: asks whether the inventor had public information that “persuaded him that he could reasonably expect to achieve the desired result.” No ambiguity here. Focuses on the inventor’s state of mind.
Non-obviousness and invention are not synonymous.
You do teach this subject, right?
Anon, Are you disagreeing with the Supreme Court’s statement in Graham v. Deere?
“We have concluded that the 1952 Act was intended to codify judicial precedents embracing the principle long ago announced by this Court in Hotchkiss v. Greenwood, 11 How. 248 (1851), and that, while the clear language of § 103 places emphasis on an inquiry into obviousness, the general level of innovation necessary to sustain patentability remains the same.”
Certainly – I prefer the direct words of the authors themselves.
Self-serving dicta from the Supreme Court – especially in the face of their being smacked down by Congress (through those very same authors) – is eminently dismissible.
As a descriptive matter they certainly are synonymous, if we are referring to how courts described doctrine before the 1952 Act.
The conceptual fusion of “invention” and “an invention” is what underlies Douglas’s opinion in Funk Brothers, which ultimately leads to our current § 101 regime.
Prof “Chaos” – you have not bothered with the additional writings of those who wrote the Act of 1952, have you?
They certainly are not synonyms.
Extensively, in fact. I don’t think you’ve actually read my comment.
It’s quite simple. Prior to the 1952 Act, courts referred to the doctrine we now call obviousness as “lack of invention.” So yes, if you’re discussing a pre-52 act case, the term “invention” may mean the doctrine termed non-obviousness in the 1952 Act.
The use of the identical term for doctrines we would today call eligibility and non-obviousness bred confusion and permitted the kind of analysis seen in Funk.
I wouldn’t say DeForest really is an eligibility case though. Had free electron emission not been described in the prior art, the Court states that Langmuir’s low-vacuum triode would have been patentable. In that sense Langmuir was not the first to discover the scientific principle behind operation of the vacuum tube, though he was the first to apply it.
I did – your attempt does not make it.