The basis of this suit was a reissued patent of July 20, 1920, to the appellant Keller for claimed new and useful improvements in windshields for automobiles. The original patent to him was issued November 12, 1918, in which he stated:

Accompanying the foregoing with illustrative drawings and their explanations, the patentee made the following three claims:

In the reissued patent of July 20, 1920, the first three claims are identical with the 3 claims of the original patent^ besides which there are 20 other claims. ;

That there is nothing of a pioneer nature in Keller’s device is abundantly shown by the numerous exhibits appearing in the record of windshields and deflectors, of one kind and another, attached to automobiles long before Keller entered the field. Both his drawings and specifications show that his shield is attached to the machine by brackets that run up and down the glass, holding it at the top and bottom, whereas the appellee’s device holds the glass by means of a fixture attached to the face of the glass and which does not extend to either of its ends. That for one device to be the equivalent of another it is essential that the former must perform the same function of the latter *841 in substantially the same way is thoroughly settled law. Machine Co. v. Murphy, 97 U. S. 120, 125 , 23 L. Ed. 935 ; Werner v. King, 96 U. S. 218, 230 , 24 L. Ed. 613 ; Simplex Window Co. v. Hauser Reversible Window Co., 248 Fed. 919, 926 , 161 C. C. A. 37 ; Dey Time Register Co. v. Syracuse Time Recorder Co. (C. C.) 152 Fed. 440, 451 ; Walker on Patents, § 348; Curtis, Patents (4th Ed.) § 310.

The evidence shows that, prior to any knowledge on their part of the Keller patent, the appellees had been working on their device, and had made and sold a few of them, but subsequently learned of and became familiar with the original Keller patent, and before proceeding with the manufacture and sale of their own device, and prior to the making of the application for the reissued Keller patent, they applied to the attorneys who procured the original Keller patent for information as to whether their device was an infringement upon that of Keller, saying that they did not wish to infringe, and, being told that it would not be an infringement, they proceeded with the manufacture and sale of their own on a substantial basis. We therefore think it clear that the appellees had and have such intervening rights as were properly protected by the court below. See Coon v. Wilson. 113 U. S. 268 , 5 Sup. Ct. 537, 28 L. Ed. 963 ; Topliff v. Topliff, 145 U. S. 156 , 12 Sup. Ct. 825, 36 L. Ed. 658 ; Dunham v. Dennison, 154 U. S. 103, 111 , 14 Sup. Ct. 986, 38 L. Ed. 924 ; Auto-Piano Co. v. American Player Action Co., 222 Fed. 276 , 138 C. C. A. 38 .

The decree of the court below is affirmed.