Heat oil in heavy large pot or Dutch oven over medium-high heat. Working in batches, cook shanks until brown on all sides, about 8 minutes. Transfer shanks to plate.
Stir in wine, tomatoes, chicken broth and beef broth. Season with rosemary and thyme.
Return shanks to pot, pressing down to submerge. Bring to a boil, then reduce heat to medium-low. Cover, and simmer until meat is tender, about 2 hours.
Remove cover from pot. Simmer about 20 minutes longer.
Transfer shanks to platter, place in a warm oven.
Boil juices in pot until thickened, about 15 minutes. Spoon over shanks.