Robertson v. Blake - 94 U.S. 728 (1876)
U.S. Supreme Court
Robertson v. Blake, 94 U.S. 728 (1876)
Robertson v. Blake
94 U.S. 728
1. Reissued letters patent No. 2,145, granted to Eli W. Blake, Jan. 9, 1886, for an improvement in machines for crushing stones, and extended June 15, 1872, were not anticipated by those granted Sept. 4, 1849, No. 6,690, to Hobbs & Brown, for crushing ice, nor by those granted Jan. 3, 1854, No. 10,365, to James Hamilton, for an ore-crusher.
2. The Court sustains the validity of said letters patent to Blake, and finds that they have been infringed by the respondent.
3. In an action for the infringement of letters patent, damages must be proved, and the burden of proof is upon the complainant.
4. In this case, no license fee charged by the complainant is shown, although it appears that he made a profit of forty dollars per inch on the width of the jaws of the machines sold by him. They, however, embraced inventions covered by patents other than that for the infringement of which this suit was brought. Held that in the absence of proof to show how much of that profit was due to such other patents, and how much was a manufacturer's profit, he is entitled to nominal damages only against the respondent.
The facts are stated in the opinion of the Court.