US SUPREME COURT DECISIONS

A greater degree of liberality and a wider range of equivalents are permitted where the patent is of a pioneer character than when the invention is simply an improvement, although the last and successful step in the art theretofore partially developed by other inventors in the same field.

The patent involved in this case, for the unhairing of seal and other skins, while entitled to protection as a valuable invention, cannot be said to be a pioneer patent.

In making his claim, the inventor is at liberty to choose his own form of expression and, while the courts may construe the same in view of the specifications and the state of the art, it may not add to or detract from the claim.

As the inventor is required to enumerate the elements of his claim, no one is the infringer of a combination claim unless he uses all the elements thereof.

Where the patent does not embody a primary invention, but only an improvement on the prior art, the charge of infringement is not sustained if defendant's machines can be differentiated.

This action was begun in the Circuit Court of the United States for the District of New Jersey for the purpose of enjoining the alleged infringement of certain letters patent of the United States, issued to John W. Sutton, and bearing date of May 22, 1888, number 383,258, for a certain new and useful invention or improvement upon machines for plucking furs. chanrobles.com-red

Page 198 U. S. 400

In the circuit court, a decree was rendered granting an injunction, 120 F.6d 2; upon appeal to the Circuit Court of Appeals for the Third Circuit, this judgment was reversed and the cause was remanded to the circuit court with directions to dismiss the bill. 123 F.8d 9.

The case was brought here upon writ of certiorari to review the judgment of the circuit court of appeals.