Wittek will forego spring practices with the Trojans under coach Steve Sarkisian.
Due to NCAA rules, Wittek will be eligible to play at another university immediately upon graduating from USC. He will have two years of eligibility remaining.
Wittek served as the third-string quarterback his freshman season, while backing up Matt Barkley in 2012.
Late in the Trojans' 2012 7-6 season, he was inserted in the fourth quarter against UCLA when Barkley went down with a shoulder injury.
USC fell to the Bruins, 38-28.
He battled for the starting position in 2013 against fellow redshirt sophomore Cody Kessler.
Former coach Lane Kiffin allowed the competition to continue through the first two games of the season, with Wittek coming off the bench to replace a starting Kessler in both contests.
Kiffin said neither quarterback separated himself from the other.
After the first two games, however, Kiffin chose to name Kessler the sole-quarterback of the 2013 team.
Wittek played sparingly through the rest of the Trojans' 10-4 2013 season.
Wittek told the LA Times he hasn't spoken to any prospective schools as he waits for permission-to-contact paperwork from USC.
Part of the 2011 recruiting class, Wittek graduated from Santa Ana (Calif.) Mater Dei and was a four-star recruit; the No. 11 rated quarterback in the class.
Kessler, also part of the 2011 recruiting class, was a four-star recruit as well. He was rated the No. 12 quarterback in the class.
With Wittek's departure from the team, the Trojans will go through spring practices with returning starter Kessler, redshirt freshman Max Browne, and freshman Jalen Greene.
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