Remove and discard the giblets and neck from the chicken. Rinse chicken with cold water; pat dry.
Starting at the neck cavity, loosen skin from the breast and drumsticks by inserting fingers, gently pushing between the skin and meat.
Combine soy sauce, ginger, garlic, green onions, and broth in a large heavy-duty zip-top plastic bag. Add chicken; seal and marinate in refrigerator 4 to 8 hours, turning bag occasionally. Remove chicken from bag, reserving 1/2 cup marinade.
Boil the marinade in a small saucepan for about 2-3 minutes, and set aside.
Preheat oven to 375 degrees.
Place chicken, breast side up, on a roasting pan. Insert the meat thermometer into the meaty part of the thigh, making sure not to touch the bone.
Roast in the oven for 1 hour and 10 minutes, basting the bird with the reduced marinade sauce every 15-20 minutes, until the thermometer registers 165-170 degrees.
Remove from heat and cover chicken loosely with foil; let stand 10 minutes for the chicken to reabsorb juices.