Patent model

A patent model was a handmade miniature model no larger than 12" by 12" by 12" (approximately 30 cm by 30 cm by 30 cm) that showed how an invention works. It was one of the most interesting early features of the United States patent system.

Since some early inventors had little technological or legal training, it was difficult for them to submit formal patent applications which require the novel features of an invention to be described in a written application and a number of diagrams.

In the US, patent models were required from 1790 to 1880. The United States Congress abolished the legal requirement for them in 1870, but the U.S. Patent Office (USPTO) kept the requirement until 1880.

On July 31, 1790 inventor Samuel Hopkins of Pittsford, Vermont became the first person to be issued a patent in the United States. His patented invention was an improvement in the "making of Pot Ash by a new apparatus & process." These earliest patent law required that a working model of each invention be produced in miniature.

Some inventors still willingly submitted models at the turn of the twentieth century. In some cases, an inventor may still want to present a "working model" as an evidence to prove actual reduction to practice in an interference proceeding. In some jurisdictions patent models stayed an aid to demonstrate the operation of the invention. In applications involving genetics, samples of genetic material or DNA sequences may be required.

The United States Patent Office used to publicly display the models of approved patents.

The United States Patent Office's collection of models have suffered two major fires- one in 1836, and another in 1877. The 1877 fire destroyed 76,000 patent models.

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Wikipedia