Benjamin N. Cardozo

“ From all this it results that a stranger to a patent suit does not avoid altogether the consequences of a judgment rendered in his absence by establishing his privilege under the doctrine of res judicata to try the issues over again. If he has that opportunity and there is substantial identity of evidence, he may find that the principle of adherence to precedent will bring him out at the end where he would be if he had been barred at the beginning. ”

“ For the purpose of any controversy between Armstrong and De Forest, the validity of the patents must be accepted as a datum. Even for the purpose of a controversy with strangers, there is a presumption of validity, a presumption not to be overthrown except by clear and cogent evidence. The question is whether the respondent has sustained that heavy burden. ”

“ Be that as it may, the requirement of evidence sufficient to carry conviction to the mind is little more than another form of words for the requirement that the presumption of validity shall prevail against strangers as well as parties unless the countervailing evidence is clear and satisfactory. ”

“ The petitioners, after repelling every assault from within the ranks of rival claimants, found it necessary to meet a challenge from without. The respondent, Radio Engineering Laboratories, Inc., allying itself with Armstrong, who is paying its expenses, insists that the invention is at large for the reason that De Forest, who received the patents, is not the true inventor, and that Armstrong, who is the inventor, is barred by a final judgment, conclusive between himself and the pretender, from obtaining the patent that is due him, and with it an exclusive right. ”

“ The respondent, defendant in the trial court, admits the infringement if the patents are valid, but maintains that they are void in that they were issued to a patentee who was not the first inventor.
Long before this suit the rival claimants to the invention, Armstrong and De Forest, had fought out between themselves the legal battle now renewed. The outcome of their contest was a decree whereby priority of invention was found in accordance with the patents now assailed by the respondent, a decree binding on the claimants and their several asignees. ”

“ A patent regularly issued, and even more obviously a patent issued after a hearing of all the rival claimants, is presumed to be valid until the presumption has been overcome by convincing evidence of error. The force of that presumption has found varying expression in this and other courts. Sometimes it is said that in a suit for infringement, when the defense is a prior invention, 'the burden of proof to make good this defense' is 'upon the party setting it up,' and 'every reasonable doubt should be resolved against him.' Cantrell v. ”

“ At the outset there were four claimants to priority of title. All four, acting independently, had made the same or nearly the same discovery at times not widely separate. The prize of an exclusive patent falls to the one who had the fortune to be first. ”

“ On August 6, 1912, a diagram showing a feed-back hook-up of the input and output circuits is recorded in Van Etten's notebook with a note that by the use of the coupling 'a beautiful clear tone' had been developed, which means that oscillations had been produced and that the oscillations were sustained. There is also a note that the pitch, i.e., the frequency, was varied by altering the plate voltage, which means, or was understood, we are told, by De Forest to mean, that by other simple adjustments the frequency of the oscillations could be varied at will. ”

“ What Armstrong does deny is that anything done or recorded in August, 1912, is an anticipation of his own invention. He says that the sustained oscillations generated at that time were of audio and not of radio frequency, and this, it seems, is admitted. He says there was then no perception or thought that the audion plate could be made to oscillate at radio as well as audible frequencies through a coupling of the circuits. This De Forest denies. ”

“ The others gain nothing for all their toil and talents. Of the four claimants Langmuir filed an application for a patent on October 29, 1913, claiming August 1, 1913, as the date of his invention. Armstrong filed an application on October 29, 1913, and a second one on December 18, 1913, fixing the date of his invention as the fall of 1912 or the beginning of 1913. ”

“ This, he says in substance, must have been obvious upon reflection to any competent electrician, though there would be need of a certain amount of adjustment and experiment in substituting the correct inductance or capacity, a process, it is argued, that would be well within the ability of any one skillful in the art. ”