Seeborg was born in 1956 in Landstuhl town, Kaiserslautern district, Rhineland-Palatinate state, Germany.

[2] Seeborg received a Bachelor of Arts summa cum laude with a major in history from Yale University in May 1978 and a Juris Doctor from Columbia Law School in 1981.

[3][4] In 1982, Seeborg joined the San Francisco law firm of Morrison & Foerster as an associate.

[3] He served in that post until 1998, when he returned to Morrison & Foerster, working as a partner and focusing on a litigation practice in the fields of securities, intellectual property, and general commercial matters.

[4] He became chief judge on February 1, 2021, after Phyllis J. Hamilton assumed senior status.