The Du Pont family is an American family descended from Pierre Samuel du Pont de Nemours (1739–1817). The son of a Paris watchmaker and a member of a Burgundian Huguenot family, and descendant of a minor noble family on his mother's side, he and his sons, Victor Marie du Pont and Eleuthère Irénée du Pont, emigrated to the United States in 1800 and used the resources of their Huguenot heritage to found one of the most prominent of American families, and one of its most successful corporations, E. I. du Pont de Nemours and Company, initially established by Eleuthère Irénée as a gunpowder manufacturer. Various members of the family managed the company well into the twentieth century and to this day family trusts constitute a substantial portion of the company's ownership. This and other companies run by the du Pont family employ some five to ten percent of Delaware's population. The family also played a very large part in politics during the eighteenth and nineteenth centuries and were responsible for the idea of the Louisiana purchase. During the 19th century, the Du Pont family maintained their family wealth by carefully arranged marriages between first cousins which, at the time, was the norm for many rich families.

Jay Parker (July 8, 1874 – June 8, 1935) was a starting pitcher who played briefly for the Pittsburgh Pirates during the 1899 season. Listed at 5 ft 11 in (1.80 m), 185 lb., Parker batted left-handed and threw right-handed. He was born in Theresa, New York. His older brother, Doc Parker, also pitched in the majors.

Little is known about this player on a Pirates uniform. Parker was 25 years old when he entered the majors on September 27, 1899 with Pittsburgh, starting against the Chicago Orphans. His performance that afternoon at West Side Park, reduced to the bare essentials, matching his career totals: three batters, hit one, walked two, and gave up two unearned runs, without making an out to have an undefined ERA. It is sometimes incorrectly displayed as zero or as the lowest ranking ERA when it is more akin to the highest. He played through 1905, but never appeared in a major-league game again.

He had brief stints as a manager in the minor leagues in 1904 and 1914.

Parker died in Hartford, Michigan, at the age of 60.