One case that comes to mind of generic-drug litigation of process patents is Pfizer vs. Ranbaxy's over two Lipitor patents #6,087,511 and #6,274,740 that expire in 2016.
Another case that was settled with several generics is Sepracor's Xopenex nebules which is protected by few method of use patents expiring until 2013 and one process patent #6,451,289 that expire in 2021.