(dissenting).
The District Judge, I think, correctly held the claims 3, 4, 5, 9 and 10 of the Matthews patent, Re. 21,003, to be valid, but not infringed by the defendant’s awnings, which were made under license from the owners of the Houseman patent, Re. 20,925, and in strict conformity to claims 11, 12, 13, 14 and 15 thereof. The deference due to the expert judgment of the Patent Office, under the evidence in this case, fairly requires both conclusions. Our disagreement relates only to the matter of infringement. The Patent Office conclusions ought to be followed as to that matter too. This is not to say that a real infringement of a senior patent can be justified because it appears to be authorized by a junior patent. It may often happen that *41by inadvertence in the Patent Office the claims of a junior patent may overlap a senior patent. But here there wa,s no inadvertence. Interference proceedings were instituted between these patents, and claims 3, 4, and 5 of Matthews were, we are informed, written by the Patent Office and suggested to both parties and then were awarded to Matthews as prior inventor. Claim 3, which is typical, is: “3. A slatted awning and drain comprising in combination with two spaced end rails, an upper series of parallel slats spaced apart and fastened in right angular relation with said rails, a lower series of parallel slats secured in staggered relation with the upper series and being fastened in right angular relation with said rails, said upper and lower slats being spaced horizontally and in overlapping relation and forming horizontal air passages and longitudinal drains, means for mounting said awning with the slats positioned lengthwise, said drains being designed to permit through passage of rainwater away from the endwise face adjacent to the wall and to discharge through the endwise face of the awning at the end spaced from the wall.” Now as a result of the same interference Houseman, though junior, was awarded claims of which 11 is typical: “11. In an awning of the class described, (that is, a sheet metal awning with crossbars and lateral spaced roof plates), the combination of a series of lower spaced parallel plates having upstanding flanges mounted on a support adapted to be attached to a wall or the like in combination with a series of overlying, spaced, parallel staggered plates having depending flanges, said upper plates being mounted on said support, closely spaced to one another and in close spaced parallel relationship with the lower plates whereby the depending flanges of the upper plate together with a lower staggered plate obstructs all direct rays of light coming over the edge of a succeeding upper plate.” Claim 12 speaks of the upper and lower plates as overlapping. Now each awning as described in the disclosures is a slanting roof of wooden “slats” in Matthews, and metal “plates” in Houseman, spaced apart, and with an upper series covering the spaces of the lower, but lifted so as to allow the escape of hot air from beneath the awning. Matthews’ “slats” have shallow grooves to carry off the water, but he states they may be made of metal, and corrugated metal would be a plain equivalent. Houseman’s “plates” of metal are similarly spaced, though secured differently, but instead of shallow grooves to carry the water they have upturned flanges on the lower plates which make each a water trough or gutter during a rain. His upper plates have the edge reaching below the upper edge of flanges pointing downward, their lower edge reaching below the upper edge of the upturned flanges, so that while the hot air can rise over' the latter and pass under the former and so escape, no sunshine can pass through, and no rain, even though it comes down almost horizontally. Matthews’ own patent drawings show that while the air can escape without obstruction laterally between his upper and lower slats, slanting sun rays or raindrops will also go down between them.
The reconciliation of these claims lies in this — each is expressly for a combination only, and such patents are to be narrowly construed. To interfere or to infringe, each element of the combination must be used or substituted by an equivalent “well known as such at the date of the patent.” Rowell v. Lindsay, 113 U.S. 97, 5 S.Ct. 507, 28 L.Ed. 906. “On the other hand if the substituted element was new, or performed substantially a different function, or was not known at the date of plaintiff’s patent as a proper substitute for the one omitted, he does not infringe.” 40 Am.Jur., Patents § 164, and cases cited in note 7. Both these patents grow out of the ancient plank top porch over the front door and windows of the humble home, where on two rails a lower series of planks slanting from the house were nailed, and the cracks between them covered by another series of planks. Though at first nailed down tight, it is common knowledge, at least to one raised in the country, that the weather will soon warp the planks, and turn thei-r edges up, so that each is a channel for water; and at the same time will open cracks between the upper and lower planks through which wind-driven rain may enter, or heated air escape. There could be no broad patent on *42a roof or awning of such a general construction. The inventions here are narrow, not basic, and consist in the specific adaptations made of “roof planks” to cut off rain and sunshine and let -hot air escape. Matthews has used flat, grooved planks, mounted in one way and allowing a maximum ventilation at a sacrifice of protection against sunshine and rain. Houseman has used metal planks differently mounted and with up and down flanges overlapping so that no sunshine or rain can pass, but air can, though somewhat obstructed laterally. There is enough difference in function to say the combinations do not interfere.
Certainly the Patent Office so held. In a close case we should follow their lead. In Miller v. Eagle Mfg. Co., 151 U.S. 186, on page 208, 14 S.Ct. 310, on page 319, 38 L.Ed. 12 we read: “The issuance of the patents to Gardiner & Downey, Berlew and Kissell, and Elder creates a prima facie presumption of a patentable difference from that of the Wright patent of 1879.” And in Boyd v. Janesville Hay Tool Co., 158 U.S. 260, 261, 15 S.Ct. 837, 39 L.Ed. 973, it is said: “As both applications were pending in the patent office at the same time, and as the respective letters were granted, it is obvious that it must have been the judgment of the officials that there was no occasion for an interference, and that there were features which distinguished one invention from the other. In American Nicolson Pavement Co. v. Elizabeth, 4 Fish. Pat.Cas. 189, Fed.Cas.No.312, Mr. Justice Strong said: “The grant of the letters patent was virtually a decision of the patent office that there is a substantial difference between the inventions. It raises the presumption that according to the-claims of the later patentees, this invention is not an infringement of the earlier patent.” This court might well follow the Supreme Court in thus recognizing the decision of the Patent Office here, thus deliberately made. Other courts have done so. Hoppenstand v. Mack Corporation, 3 Cir., 89 F.2d 360; Knowles v. 138 W. 42 Street Corporation, 2 Cir., 43 F.2d 929, 930; Beldom v. Garlock Pkg. Co., D.C., 24 F.2d 852, 953; Majestic Elec. App. Co. v. Hicks, 9 Cir., 24 F.2d 165, 166.