Legal Definitions - prior-use bar

A prior-use bar is a legal term that refers to a situation where a patent cannot be granted for an invention that was publicly used or sold in the United States more than one year before the application date. This is also known as a public-use bar.

If someone invents a new type of phone and uses it in public or sells it to others more than a year before they apply for a patent, they may not be able to get a patent for that invention. Similarly, if someone creates a new type of software and shares it with others without a pledge of secrecy, they may not be able to get a patent for it if more than a year has passed since the public use or sale.

These examples illustrate how the prior-use bar can prevent someone from obtaining a patent for an invention that has already been publicly used or sold. It is important for inventors to be aware of this rule and to apply for a patent as soon as possible after creating their invention.