The lawsuit says Matthew Crozier of Yardley fell 30 feet from a stairway at Phi Kappa Sigma house on Jan. 1, 2011.
The suit alleges that the underage Crozier was allowed to drink at the party and buy beer earlier at a Bucks County store.
Crozier, the son of David and Helene Crozier, had been a student-athlete at John Carroll University in Ohio.
Family lawyers say the settlement includes $3 million from the fraternity and $375,000 from Suds Beer Store of Trevose, and undisclosed terms with Penn.
A Penn spokeswoman says the university cannot comment on the confidential settlement.