C. Marshall Dann


C. Marshall Dann was born in Wilkinsburg, Pennsylvania, on March 27, 1915. His father was an engineer with Westinghouse Electric Corp. He received a bachelor’s degree in chemistry from Worcester Polytechnic Institute, a master’s degree in chemistry from the University of Delaware, and a law degree from Georgetown University.

He spent 36 years with E.I. du Pont de Nemours & Co., at the time the world’s largest chemical company. He started as a research chemist in Wilmington, Delaware, and was named as the inventor in a U.S. patent. He decided to take advantage of a DuPont program in Washington, D.C., that allowed employees to work in the company’s Washington office as patent apprentices while attending law school. Many large companies ran apprentice programs during that era. After law school he returned to Wilmington and rose to the position of chief patent counsel of the company, managing more than 100 patent lawyers. 

President Richard Nixon appointed Dann commissioner of patents, and he took the oath of office on February 11, 1974. Congress changed his title to Commissioner of Patents and Trademarks in 1975 when it changed the office’s name to the Patent and Trademark Office to recognize its trademark functions. Dann advocated the name change.

In 1974 the office began new programs to maintain and improve the quality of patent examination. First, it established a quality review program to evaluate the quality of a sample of patent applications before a patent was granted. Second, it developed an experimental program under which a sample of 2,000 patent applicants were invited to expose their applications to public protest proceedings before a patent was granted.

During Dann’s tenure the one millionth U.S. trademark was registered, in 1974, and patent number 4,000,000 was granted in 1976 under the patent numbering system begun in 1836. 

Under Dann the office adopted major changes in the rules governing patent applications and patents. Dann proposed the rules, known as the “Dann Amendments,” to achieve changes in patent practice by rulemaking that resembled, but was less far reaching than, changes proposed in a controversial bill that failed to pass Congress.

The Dann Amendments allowed patent owners to file a “no defect” reissue patent application to test the validity of a patent when the original claims might be invalid. Later, after Congress enacted a patent reexamination law in 1980, the no defect reissue procedure was eliminated. The Dann Amendments also codified a duty by patent applicants to inform the office of prior art they were aware of that might affect the validity of their patents. This requirement would undergo several changes in succeeding years. 

Another rule change authorized patent examiners to make of record their reasons for allowing a patent application. The Federal Register published the final version of the Dann Amendments on January 19, 1977, the last day before President Jimmy Carter took office.

Several patent and trademark treaties and other international agreements were negotiated or came into effect during Dann’s tenure. The United States ratified the landmark Patent Cooperation Treaty on November 26, 1975, five years after it had been negotiated in Washington. A treaty was negotiated in 1977 in Budapest, Hungary, on samples of microorganisms submitted in connection with patent applications. Also, a diplomatic conference was held in Geneva, Switzerland, in 1977 to revise the Nice Agreement on trademark classification. 

In 1977 the average pendency of patent applications was reduced to 18.9 months, the shortest time in many years. Also in 1977, the USPTO opened a new microfilm center in the patent public search room and installed a computer system in the trademark search room for updating records to replace a cumbersome hand stamping procedure. The system also provided information on the status and location of pending trademark applications.

Dann resigned on August 31, 1977, after the election of President Carter, and became a partner in a Philadelphia law firm. He testified as an expert in 45 patent infringement trials in district courts throughout the United States and served as an arbitrator in patent cases. He died in Wilmington, Delaware, on April 24, 2002, at the age of 87.



Bloomberg BNA, Weekly Patent, Trademark & Copyright Journal (1974-1977).

USPTO, Annual Reports of the Commissioner of Patents (1974-77).

USPTO, The Story of the U.S. Patent and Trademark Office (1988).