concurring in part and dissenting in part.

I concur in the judgment and in all of Judge Alarcon’s thorough opinion except its treatment of the requirement of “syner *690 gism”. I have no difficulty joining the majority in rejecting any implied suggestion that (1) validity of a combination patent depends in any literal sense upon the combination’s amounting to more than the sum of its parts, and (2) obviousness is to be judged with the benefit of hindsight, in light not only of the prior art but also of the disputed innovation itself. In rejecting these propositions, however, I would not reject the concept of “synergism” as well, because I do not understand our prior decisions to have equated the synergism requirement with the rejected propositions. In Penn International Industries v. Pennington Corp., 588 F.2d 1078 (9th Cir. 1978), for example, this court required a combination patent to be “synergistic”, which it equated with the well-recognized requirement that the combination produce “ ‘an unusual or surprising result’ ”. Id. at 1081 . In so ruling, the court clearly viewed its requirement of synergism as a proper formulation of the nonobviousness standard of § 103, as that standard was interpreted in Graham v. John Deere Co., 383 U.S. 1 , 86 S.Ct. 684 , 15 L.Ed.2d 545 (1966). A similar approach was taken in Satco, Inc. v. Transequip, Inc., 594 F.2d 1318, 1322 (9th Cir. 1979) and Hershensohn v. Hoffman, 593 F.2d 893 , 897 (9th Cir. 1979). As the term is used in these cases, the “synergism” requirement merely restates the correct and rigorous requirement of nonobviousness for combinations of old elements. The same usage is reflected in Sakraida v. Ag Pro, Inc., 425 U.S. 273, 279 , 96 S.Ct. 1532, 1536 , 47 L.Ed.2d 784 (1976) and Anderson’s-Black Rock, Inc. v. Pavement Salvage Co., Inc., 396 U.S. 57, 61 , 90 S.Ct. 305, 308 , 24 L.Ed.2d 258 (1969). That other, less defensible meanings may also be ascribed to the term is not a sufficient reason for discrediting “synergism” in all its applications. I would therefore avoid the risk of being misunderstood to be weakening the standard of patentability for combinations of old elements, and would leave the doctrine of synergism where we found it. It is not necessary to attack the doctrine to sustain the judgment in this case; Sarkisian’s patent meets the synergistic standard. The majority opinion’s discussion of Sarkisian’s device in the light of prior art and of the state of skill in the field supports that conclusion. We need do no more.

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