The X-Patents are all the patent

Patent

A patent is a form of intellectual property. It consists of a set of exclusive rights granted by a sovereign state to an inventor or their assignee for a limited period of time in exchange for the public disclosure of an invention....

s issued by the United States Patent and Trademark Office

United States Patent and Trademark Office

The United States Patent and Trademark Office is an agency in the United States Department of Commerce that issues patents to inventors and businesses for their inventions, and trademark registration for product and intellectual property identification.The USPTO is based in Alexandria, Virginia,...

 from July 1790 (when the first U.S. patent was issued), to July 1836. The actual number is unknown, but the best estimate is 9,957. The records were burned in a fire, in December 1836, while in temporary storage. No copies or rosters were maintained by the government at the time, leaving only the inventors’ copies to reconstruct the collection.

The USPTO and its earliest days

The Patent Commission of the U.S. was created in 1790. Its first three members were Secretary of State

Secretary of State

Secretary of State or State Secretary is a commonly used title for a senior or mid-level post in governments around the world. The role varies between countries, and in some cases there are multiple Secretaries of State in the Government....

 Thomas Jefferson

Thomas Jefferson

Thomas Jefferson was the principal author of the United States Declaration of Independence and the Statute of Virginia for Religious Freedom , the third President of the United States and founder of the University of Virginia...

, Secretary of War Henry Knox

Henry Knox

Henry Knox was a military officer of the Continental Army and later the United States Army, and also served as the first United States Secretary of War....

, and Attorney General

Attorney General

In most common law jurisdictions, the attorney general, or attorney-general, is the main legal advisor to the government, and in some jurisdictions he or she may also have executive responsibility for law enforcement or responsibility for public prosecutions.The term is used to refer to any person...

 Edmund Randolph

Edmund Randolph

Edmund Jennings Randolph was an American attorney, the seventh Governor of Virginia, the second Secretary of State, and the first United States Attorney General.-Biography:...

.

On July 31, 1790 inventor Samuel Hopkins

Samuel Hopkins

Samuel Hopkins may refer to:*Samuel Hopkins , American inventor who was awarded the first US patent for a process to refine potash...

 of Pittsford, Vermont

Pittsford, Vermont

Pittsford is a town in Rutland County, Vermont, United States. The town was named for William Pitt. As of the 2010 census, the town population was 2,991. Pittsford was first settled as a frontier town in 1769, about north of Bennington...

 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

Potash

Potash is the common name for various mined and manufactured salts that contain potassium in water-soluble form. In some rare cases, potash can be formed with traces of organic materials such as plant remains, and this was the major historical source for it before the industrial era...

 by a new apparatus & process.” The earliest patent law required that a working model

Patent model

A patent model was a scratch-built miniature model no larger than 12" by 12" by 12" that showed how an invention works...

 of each invention be produced in miniature.

The Patent Law was revised for the first time in 1793. It adopted a simple registration system where a patent would be granted for a $30 fee. The Patent Board was replaced by a clerk in the Department of State. James Madison

James Madison

James Madison, Jr. was an American statesman and political theorist. He was the fourth President of the United States and is hailed as the “Father of the Constitution” for being the primary author of the United States Constitution and at first an opponent of, and then a key author of the United...

, Secretary of State, created a separate Patent Office within the State Department and he appointed Dr. William Thornton

William Thornton

Dr. William Thornton was a British-American physician, inventor, painter and architect who designed the United States Capitol, an authentic polymath...

 as its first superintendent in May 1802.

The Patent Office was the only major government building to survive the British invasion of Washington, D.C.

Washington, D.C.

Washington, D.C., formally the District of Columbia and commonly referred to as Washington, "the District", or simply D.C., is the capital of the United States. On July 16, 1790, the United States Congress approved the creation of a permanent national capital as permitted by the U.S. Constitution....

 during the War of 1812. This is credited to Dr. William Thornton who was building a musical instrument in the same building. He persuaded British officers that they would be destroying the shared intellectual record of mankind if the patents were burned.

The 1836 fire

The disastrous fire occurred on December 15, 1836, when the patents were in temporary storage while a new (more fireproof) facility was being built. A fire station was located next to the temporary storage facility, but the hoses and pumps were frozen, and the firemen were unable to prevent the loss.

Recovery of the X-Patents

The United States Congress

United States Congress

The United States Congress is the bicameral legislature of the federal government of the United States, consisting of the Senate and the House of Representatives. The Congress meets in the United States Capitol in Washington, D.C....

 immediately passed a law to aid re-issuing of the missing patents after the fire. About 2,800 such patents have been recovered, and 1,989 are online.

Following the 1836 fire, a serial numbering system was instituted. This system is still in use today. When an earlier patent was recovered and re-issued, the USPTO sometimes gave it a fractional number (eg. 2960½X, issued on June 2, 1818; 8736¾X, issued on March 27, 1835) to preserve the correct sequence. Most, but not all, fractional patents are X-Patents.

Prior to this, U.S. patents were identified by titles and dates. Since then, all new patents issued are preserved and given a serial patent number started from 1. The recovered patents are also numbered from 1, however, these numbers have an “X” added to them. The X is generally added to the end of the number except for the first patent which has the X in the beginning of the number. Therefore, they are called X-Patents.

The latest X-Patents were recovered in 2004 from the Dartmouth College

Dartmouth College

Dartmouth College is a private, Ivy League university in Hanover, New Hampshire, United States. The institution comprises a liberal arts college, Dartmouth Medical School, Thayer School of Engineering, and the Tuck School of Business, as well as 19 graduate programs in the arts and sciences...

 archives. Of the 14 found, 10 were granted to Samuel Morey

Samuel Morey

Samuel Morey was an American inventor, who worked on early internal combustion engines and was a pioneer in steamships who accumulated a total of 20 patents.-Early life:...

 including the first known patent for an internal combustion engine

Internal combustion engine

The internal combustion engine is an engine in which the combustion of a fuel occurs with an oxidizer in a combustion chamber. In an internal combustion engine, the expansion of the high-temperature and high -pressure gases produced by combustion apply direct force to some component of the engine...

.

A list of some X-Patents

Patent	Invention	Inventor	Date
1X	Potash production	Samuel Hopkins	July 31, 1790
72X	Cotton Gin	Eli Whitney	March 14, 1794
4378X	Gas Or Vapor Engine	Samuel Morey	April 1, 1826
9000X	Grate	N. Winslow	July 2, 1836
9899X	Brick Machine	C. Waterman	July 2, 1836
9894X	Plow Moldboard	I. Snider	July 2, 1836
9893X	Lock	A. Roff	July 2, 1836
9890X	Thrashing Mach.	A. Parson	July 2, 1836
9889X	Cook Stove	W. Parmalee	July 2, 1836
9887X	Plow	T. Miller	July 2, 1836
9886X	Dressing Stares	C. McGregory	July 2, 1836
9885X	Cotton Gin	J. McCreight	July 2, 1836
9884X	Door Lock	J. Mo Clory	July 2, 1836
9882X	Clover Huller	W. Loomis	July 2, 1836
9879X	Feather Dresser	F.P.Knowlton	July 2, 1836
9878X	Platform Balance	J. Horton	July 2, 1836
9877X	Nail Extractor	R. Haynes	July 2, 1836
9876X	Cotton Press	H.G. Guyon	July 2, 1836
9875X	Cook Stove	C. Granger	July 2, 1836

External links

• X-Patents Online at USPTO Website
• Interesting Patent Events
• The U.S. Patent No. 1X
• “Patent Models’ Strange Odyssey” by Teresa Riordan, The New York Times, February 18, 2002.
• Early patent records found in library