Marcelles Peter, 20, and Jose Montano, 22, could spend as much as 33 years in prison, the Contra Costa County Times reported Thursday.
The men have been in jail since their arrests nearly four years ago. They are the third and fourth people convicted in connection with the crime.
Prosecutors had charged all four men beat, raped and sexually abused the teenager in a dark campus courtyard at Richmond High School for more than 2 hours as a crowd looked on.
The girl was hospitalized in a coma, but survived.
Poole and Montano were found guilty by separate juries of rape in concert, sexual penetration in concert and oral copulation in concert.
Thirty witnesses testified during the six-week trial, including two other men convicted in the rape, who are awaiting trial.