 Duryea had been a prominent owner and breeder of racehorses in New York State, until 1908.In that year, gambling was made illegal in the state by the Hart–Agnew Law, forcing most racetracks to close, and like several of his compatriots Duryea transferred his racing and breeding operations to Europe.Shortly afterwards and possibly in response to the influx of American horses, the Jockey Club created a new regulation which became known as the Jersey Act, banning horses without proven “pure” descent from foundation mares from being registered in the General Stud Book.