Thе plaintiff sued the defendant for in- - fringement of patent No. 1,501,325, issued on July 15, 1924, to Thomas Elliott, and included two others in the bill. We held the patent just mentioned, and one of the others infringed; the third, not infringed. Cincinnati Car Co. v. New York Rapid Transit Co.,
The chief question is whether the plaintiff is entitled to an accounting for profits. Elaborate calculations have been made, based upon the earnings of thе road out of the infringing trains, as well as upon the savings from their substitution; but both assume that the profits are to be allocated to the invention alone. The supposititious increase in fares was clearly too speculative. Added fares, due to the larger accommodation for passengers of a trаin of three articulated cars over two unartieulated, presuppose that passengers, who could not have boarded unarticulated ears, would have left the subway, or not have entered because of the crowds. That would indeed have been a happy consummation, but there is no reason to assume it. That the road took in more fares than it would otherwise have done, must remain a conjecture on which we cannot base an award. More could be said for the initial saving in the eost of the articulated trains, if they had been patented as a whole. While it might indeed be illegitimate to include in the saving more than that upon the bare frame of the cars without fittings, on the other hand, it might be proper to add the decrease in cost of upkeep, had that been properly proved. Some fair measure of equivalency in accommodation was estab *593 lished between the two systems, and we will not say that if the defendant was liable for profits on the trains as a whole, it was not possible to fix the savings.
The situation was not that, however, but one so common in patent accountings, in which the invention is not of the article as a whole, but-of a small detail. The difficulty of allocating profits in such eases has plagued the courts from the outset, and will continue to do so, unless some formal and conventional rule is laid down, which is not likely. Properly, the question is in its nature unanswerable. It is of course possible to imagine an invention for a machine, or composition, or process, which is a complete innovatiоn, emerging, full grown, like Athene, from its parent’s head. It would then be easy to say that profits were to be attributed wholly to the inventi.on. Such inventions are however mythological. All have a background in the past, and are additions to the existing stock of knowledge which infringing articles embody along with the invention. It is generally impossible to allocate quantitatively the shares of the old and the new, and the party on whom that duty falls, will usually lose. If the patentee is required to assess the contribution of his invention to the profits, he will find it impossible; vice versa, if this is demanded of the infringer. The burden of proof in such cases is the key to the result.
Before Westinghouse Co. v. Wagner Co.,
We do not think that Westinghouse Co. v. Wagner Cо., supra, 225. 17. S. 604,
Nevertheless, there always remains the inquiry when the invention covers the whole article, and when it is only for an improvement. Once it be agreed that the mere text of the claims does not determine this, the answer must be in terms of degree and cannot he fonnd a priori. As we have already said, in practice all inventions are for improvements; аll involve the use of earlier knowledge; all stand upon accumulated stores of the past. Often, perhaps generally, the test will be structural, as for example, whether the addition cannot be isolated as a separate physical part; though that is by no means a final test. Be that as it may, the doctrine cannot be more particularly stated, and was in substance so declared, as we apprehend, in Westinghouse Co. v. Wagner Co., supra, 225 17. S. 604,
In Van Kannel Revolving Door Co. v. Uhrich,
The burden of proof must fall on one side or the other; in eases of improvement we are not satisfied that it' shifts to the infringer, merely by showing that the improvement was necessary to the use or sales. But we need not commit ourselves, because here at any rate the road could have continuеd to use unarticulated trains. That was not indeed quite the same use; it was a substitute, and a less desirable one. But by hypothesis an improvement always somewhat modifies the prior art, and is an improvement only because its use is different. If we were to press the supposed doctrine to an extreme, every improvement patent would fall within it, for the especial use would not be answered by anything but the improvement. Either it must be confined to the seizure of the plaintiff’s market, in which case it is properly relevant only to damages; or it must be limited to cases where there is no close substitute. We hold that the burden was not upon thе defendant, and that the plaintiff has failed to establish a case for the recovery of profits.
There was no proof of damages. Both sides agree that there was no established royalty, and the only possible position for the plaintiff is that it lost the contract. However, there is no reason to suppose that it. would have got the job on its own terms. True, it was properly equipped to perform it, and the railroad’s engineer went to its factories and studied its designs. He was certainly1 interested in, and made some use of, the patented device, but that is very far from saying that the defendant would have accеpted the plaintiff as its manufacturer, had it observed the patent. The parties had never come even to the point of negotiating a contract. Several alternatives were open to the railroad. It might have got a license; indeed the only evidence is that before infringement one wаs offered on easy terms. The plaintiff’s past treatment of infringers does not suggest that it would have held out for high tribute; it was scarcely in a position to do so. Or, the railroad might have set about devising an articulation which should avoid the claims. It succeeded, when forced by us to do so. We do not mean that such a struсture may be used as a “standard of comparison” to limit profits. Perhaps not. Western Glass Co. v. Schmertz Wire Glass Co.,
The plaintiff had made five settlements, four of them after infringement, and upon all of its three patents, one of which we declared uninfringed. These license fees ranged from $250 to $75. The whole notion of a reasonable royalty is a device in aid of justice, by which that which is really incalculable shall be approximated, rather than that the patentee, who has suffered an indubitable wrong, shall be dismissed with empty hands. It is no more impossible to estimate than the damages in many other torts, as for example, persоnal injuries with their accompanying pain and mutilation. Though the testimony of experts was recognized as competent in Dowagiac Mfg. Co. v. Minnesota Plow Co., supra,
Decree modified in accordance with the foregoing.
