According to
William Poundstone's 1986
Bigger Secrets,
Robert Klark Graham's backyard sperm bank wasn't all that. William Shockley (best known, beyond his Nobel award, for his
belief in the genetic inferiority of blacks, as compared to whites) was the only
Nobel laureate who admitted to contributing, and as of 1986 the oldest contributors in the catalogue were born in the '20's. Shockley was born in 1910.
Poundstone, working with Graham's claim in 1980 to the Los Angeles Times that there were (at that time) three Nobel laureates' sperm on tap, narrowed the list down to the following likely candidates for the two laureates besides Shockley: William Giauque, Donald Glaser, Robert Hofstadter, Joshua Lederberg, Glenn Seaborg, and Emilio Segre. Poundstone then goes on to note that none of these men match any of the descriptions in the Repository's catalogue. Between '80 and '86, Graham seems to have run dry of any Nobel sperm.
In the meantime, Graham broadened his horizons and started accepting sperm donations from "acclaimed businessmen" and Olympic athletes. Based again on catalogue descriptions, Poundstone draws a tentative conclusion that gold medalist rower Brad Alan Lewis may have been a contributor.