(dissenting), with whom RICH, J., joins.
The majority opinion treats as the “principal issue” the question “whether the substitution of chlortetracycline for streptomycin in Waksman’s process would be obvious to one of ordinary skill in the art.”
While this issue must necessarily be considered, I do not consider it to be the “principal issue,” nor for that matter, determinative. Rather, I think the determinative issues are two: namely, would it have been obvious, in view of the prior art, 1) that chlortetracycline would inactivate the microorganism of chronic respiratory disease (PPLO) without harming the Newcastle disease virus, and 2) that such inactivation would be most effectively accomplished by adding the chlortetracycline to a suspension of harvested virus rather than to a fertile egg.
To summarize the facts here, the claimed method removes the danger of introducing resistant strains of PPLO into a vaccine and this is accomplished by introducing chlortetracycline in specified amounts into the live virus after harvesting the vaccine, followed by a short incubation period. The result is that the chlortetracycline selectively kills the PPLO virus without adversely affecting the Newcastle disease virus in the vaccine.
The majority position, with which I do not agree, is:
“ * * * The use of an antibiotic for selectively killing PPLO in the production of the virus fowl vaccine being old, we think it is no more than an obvious alternative to apply the antibiotic to the harvested vaccine instead of adding it to the embryo earlier in the process.”
In such a highly technical field as that with which we are here concerned, it is, I think, a serious error to dispose of the determinative issues on the basis stated in the majority opinion that
“ * * * Waksman alone may not ‘meet the claims,’ and therefore not be an anticipation, but Waksman, in view of Groupe and Gross, suggests what is being claimed.”
I do not believe this position will stand objective analysis. It ignores the statement in the specification that: .?
“It has now been found that live virus material for use in a vaccine or as a vaccine can be selectively sterilized to kill the chronic respiratory microorganisms without inactivating the desired virus by the addition, to an aqueous solution of the virus, of a suitable quantity of a broad band antibiotic followed by incubation of the antibiotic containing solution for a suitable period. In view of the fact that the antibiotics are customarily considered bacteriastatic materials rather than bacteriacidal, surprisingly complete sterilization of the vaccine material is obtained. This sterilization is obtained with substantially no inactivation of the live virus and, in fact, the antibiotic appears to exert a stabilizing effect on the vaccine material thus enabling it to withstand an incubation period better than would otherwise be expected.” [Emphasis added.]
The claims before us are drawn to cover the method by which chlortetracycline is added to the egg-propagated, live virus for the purpose of effecting such a selective sterilization of the live virus material in the vaccine. Thus, claim 8 calls for
“ * * * the improvement which comprises treating an aqueous suspension of the harvested virus before drying with from 125-25,000 gammas/cc. of chlortetracycline and incubating the antibiotic-containing solution for a period of from about six hours to fourteen days at a temperature of from about 0° C. to 50° C. until the aqueous suspension is free of the microorganism causing chronic respiratory disease of fowls.”
*362Claim 14 specifically includes:
“ * * * the step of preparing an aqueous suspension of chick embryo tissue in which live virus is present, adding thereto at least 50 gammas per milliliter of a tetracycline antibiotic and incubating the aqueous suspension for a period of from about six hours to 14 days with a temperature ranging from about 0° C. to 50° C. until virus-like microorganisms causing chronic respiratory disease in fowls have been inactivated.”
Claim 15 calls for
“* * -x- step of preparing an aqueous suspension of chick embryo tissue in which live Newcastle virus is present, adding thereto at least 50 gammas per milliliter of a tetracycline antibiotic and incubating the aqueous suspension for a period of from about 6 hours to 14 days with a temperature ranging from about 0° C. to 50° C. until virus-like microorganisms causing chronic respiratory disease in fowls have been inactivated.”
Claim 16 calls for
“ * * * the step of preparing an aqueous suspension of chick embryo tissue in which live virus is present, adding thereto at least 125 gammas per milliliter of chlortetracycline and incubating the aqueous suspension for a period of from about 6 hours to 14 days with a temperature ranging from about 0° C. to 50° C. until virus-like microorganisms causing chronic respiratory disease in fowls have been inactivated.”
To deny claims as specific as claims 14,15 and 16 on the disclosed novel method of selective sterilization of a live virus vaccine in this very specialized technical field requires, in my opinion, a much more convincing teaching than is to be found in the art here relied upon. The majority opinion purports to find it in Waksman in view of Groupe and Gross which “suggests what is being claimed.” The majority opinion does not point out the genesis of the suggestion and I respectfully submit that its genesis in the art before us is to be found only in the above quoted portion of appellants’ specification. I am unable to find in the art any suggestion of the claimed selective sterilization of a live vaccine after the virus has been harvested. It requires hindsight reconstruction to take Waksman’s suggestion and modify it by Groupe et al. to meet the claims. In my opinion, the majority opinion indulges in this most speculative reconstruction in a highly developed technical art wherein, however, predictability of results is very limited.
The rejection before us supports itself by repeated dependence on such terms as “suggestions,” and “mere matter of choice” and “lack of criticality.” Such statements on the ground of rejection create doubts as to the validity of the rejection. I would resolve those doubts in favor of appellant. I find additional support for so doing in the affidavits which were submitted by appellant and which show, without doubt:
(1) that the streptomycin of Waksman developed resistant strains of PPLO.
(2) that streptomycin-resistant strains of PPLO are found in domestic birds.
As stated in appellants’ brief:
“ -x- * * These Affidavits, the correctness of which is not questioned by the Patent Office, prove that streptomycin is capable of producing resistant strains of PPLO whereas the tetracycline antibiotics are not. This is not a difference in degree. It is a difference in kind because vaccines for Newcastle disease or other fowl diseases which sometimes infect a flock with roup are not saleable and are not useful. An unsafe vaccine is worthless. Kiser’s and Adler’s Affidavits show clearly this difference in kind. The tetracycline antibiotics do not develop resistant strains; streptomycin does. The Waksman reference does not deny this fact.”
*363I have not found any teaching in the cited references (and the majority opinion refers to none) prior to the filing date of appellants’ application that tetracycline antibiotics do not produce resistant strains. As pointed out in appellants’ brief:
“ * * * It is a difference of enormous practical value, namely the difference between a useful vaccine and one which is not. The immense sales of the vaccines prepared by the present process are eloquent of the practical value of this difference.”
While it is true that the Groupe article discloses that both streptomycin and chlortetraeycline killed the agents of turkey sinusitis, there is no teaching 1) that streptomycin produced resistant strains or 2) that the causative agents of PPLO and turkey sinusitis were similar. Thus at the time the application in issue was filed, the man skilled in this art, with the prior art before him, would not have known that it made any difference whether streptomycin or tetracycline was used, and there was no teaching in the art that tetracycline had the important properties 1) of not developing resistant strains and 2) was selective in its action in killing the agent which caused PPLO without killing the live but attenuated viruses desired in the vaccine.
f Thus, it seems to me that while the general method of producing such vaccines is admittedly old, the novelty of the point at which certain additional and claimed steps were taken by appellants constitutes a patentable feature of the claimed invention, particularly since such steps are carried out at a point in the vaccine production which is different from the prior art and is unobvious in view of the teachings of that art.
Should there be any remaining doubt as to the allowability of the claims, it should, it seems to me, be resolved in favor of appellants in view of the evidence of commercial success found in the Aiston affidavit filed April 5, 1956 in which it was stated:
“THAT, since June 1955 and to date the Viral and Rickettsial Production Department under my super- ■ vision has continued the production of fowl vaccines by means of said improved method;
“THAT, the production of fowl vaccines by said improved method to date, * * * totals well over a half-billion doses;
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“THAT, the above production has been sold in the United States, and abroad by the Lederle Laboratories Division of the American Cyanamid Company;
“THAT, all batches of the above vaccines released for sale had satisfactorily passed the safety and effectiveness tests approved by the Animal Inspection and Quarantine Branch of the Agriculture Research Service, U. S. Department of Agriculture ; * * * ”
For these reasons, I would reverse the appealed decision.