In the case of Washing-Machine Company v. Tool Company, the Supreme Court of the United States was asked to decide whether a patent for a washing machine was infringed upon by a tool company. The patent in question was for a washing machine that used a particular type of tool to agitate the clothes. The tool company argued that their tool was not the same as the one described in the patent and therefore did not infringe upon it. The Supreme Court found that the tool company had indeed infringed upon the patent. The Court noted that the patent was for a particular type of tool and that the tool company had used a tool that was substantially similar to the one described in the patent. The Court also noted that the tool company had not made any changes to the tool that would have made it different from the one described in the patent. The Court held that the tool company had infringed upon the patent and ordered them to pay damages to the washing-machine company. This case established the principle that a patent is infringed upon if a tool is substantially similar to the one described in the patent, even if some minor changes have been made.

Justice Field delivered the dissenting opinion in this case. He argued that Tool Company had a valid patent for its invention, and as such was entitled to exclusive rights over it. The majority opinion held that the patent was invalid because it did not meet certain requirements of novelty and utility set out by Congress. Justice Field disagreed with this conclusion, noting that while these criteria were important considerations when determining validity, they should not be used to override other evidence which showed that Tool Company's invention met all the necessary conditions for a valid patent. Furthermore, he noted that even if there were some technical deficiencies in their application or description of their invention, those issues could have been addressed without invalidating the entire patent altogether. As such, he concluded that Tool Company deserved protection from infringement on its patented product by Washing-Machine Company and should have been granted an injunction against them accordingly.