
Apatent model was a handmademiniature model no larger than 12" by 12" by 12" (approximately 30 cm by 30 cm by 30 cm) that showed how aninvention works. It was one of the most interesting early features of the United Statespatent system.[1]
Since some earlyinventors 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.[2] TheUnited States Congress abolished the legal requirement for them in 1870, but theU.S. Patent Office (USPTO) kept the requirement until 1880.[3]
On July 31, 1790, inventorSamuel Hopkins ofPittsford, Vermont became the first person to be issued a patent in the United States. His patented invention was an improvement in the "making ofPot 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 evidence ofactual reduction to practice in aninterference proceeding. In some jurisdictions patent models stayed an aid to demonstrate the operation of the invention. In applications involvinggenetics, samples of genetic material or DNA sequences may be required.

The United States Patent Office used to publicly display the models of approved patents.[4] This collection of models suffered two major fires- one in1836, and another in1877. The 1877 fire destroyed 75,000 patent models.[5]
In 1908, the Patent Office donated just over 1,000 patent models toUnited States National Museum.[6] The remaining models were packed and moved several times before Congress chose to dissolve the collection in 1926. The Smithsonian Institution was allowed to choose first from the remaining models; accessions from the Patent Office now form part of the collection of over 10,000 patent models at theNational Museum of American History.[6]

Many models were sold off by the patent office in 1925 and were purchased by SirHenry Wellcome, the founder of the Burroughs-Wellcome Company (now part ofGlaxoSmithKline). Although he intended to establish a patent model museum, thestock market crash of 1929 damaged his fortune; the models were left in storage. After his death, the collection went through a number of ownership changes; a large portion of the collection—along with $1,000,000—was donated to the nonprofit United States Patent Model Foundation by Cliff Petersen. Rather than being put into a museum, these models were slowly sold off by the foundation. Much legal wrangling, purchasing, and re-selling ensued.[7] A comparatively small number of models (4,000) were the property of the Rothschild Patent Museum until 2015, when they were transferred toHagley Museum and Library, forming a part of the museum's collection of patent models. With over 5,000 models, the Hagley's is the largest private collection, and second in size only to the Smithsonian's.[1][7][8]