We’ll probably never know how many women inventors there were. That’s because in the early years of the United States, a woman could not get a patent in her own name. A patent is considered a kind of property, and until the late 1800s laws forbade women in most states from owning property or entering into legal agreements in their own names. Instead, a woman’s property would be in the name of her father or husband.

For example, many people believe that Sybilla Masters was the first American woman inventor. In 1712 she developed a new corn mill, but was denied a patent because she was a woman. Three years later the patent was filed successfully in her husband’s name.