Steve Campbell of the Houston Chronicle is reporting that Case Keenum will petition the NCAA to allow him to seek a 6th year of eligibility. Keenum, of course, tore his ACL during Houston's week 3 game against the UCLA Bruins.
According to NCAA Rules:
A waiver of the five-year period of eligibility is designed to provide a student-athlete with the opportunity to participate in four seasons of intercollegiate competition within a five-year period. This waiver may be granted, based upon objective evidence, for reasons that are beyond the control of the student-athlete or the institution that deprive the student-athlete of the opportunity to participate for more than one season in his/her sport within the five-year period.
Keenum was already considered a borderline NFL Draft pick so it makes sense that he would do this. He will absolutely need the stage of the Senior Bowl and other pre-draft camps to show scouts that he's more than a "system quarterback." The timing of this injury made it impossible for Keenum to participate in the combine or any other camps.
I'm not sure if Keenum's application will be granted. A few weeks ago, SI's Stewart Mandel was asked whether he thought Keenum could be granted a sixth year. He said it was unlikely.
Unfortunately, it's extremely unlikely Keenum would get a sixth year. I think perhaps you're getting confused with the graduate-school waiver Jeremiah Masoli used to become eligible at Ole Miss. Masoli was only entering his fourth year of eligibility. Keenum is in his fifth, and while he got injured early enough that this year would theoretically qualify for a medical redshirt, it's negated by the fact that he already used up his redshirt year as a freshman. The general rule is you have "five years to play four," and it takes some pretty drastic circumstances to be granted a sixth year, like missing two full seasons to injury.
Keenum has done a lot for the C-USA with his play. I wish him the best in his recovery and like I hoped for Braxton Amy, I hope he gets the chance to end his collegiate career the way he wants to. Obviously, as Mandel pointed out, he may have an uphill battle ahead of him.