Seitz served as managing partner of Connolly Bove Lodge & Hutz LLP, where he practiced for more than three decades. He was the founding partner of Seitz, Ross, Aronstam & Moritz LLP. In that capacity, he regularly litigated corporate, commercial, and intellectual property cases, and advised clients on issues of Delaware corporate law.[3]
Delaware Supreme Court
Term as justice
On February 23, 2015, Governor Jack Markell nominated Seitz to be a justice of the Delaware Supreme Court to the seat vacated by Henry du Pont Ridgely who retired on January 31, 2015.[3] He was sworn in on April 14, 2015.
Chief justice
On October 24, 2019, Governor John Carney announced Seitz as his nominee to be the next Chief Justice of the Delaware Supreme Court.[4] On November 7, 2019, his nomination was confirmed unanimously by the Delaware Senate.[5] He was sworn into office on November 8, 2019.[6]