In a mixing bowl, whisk together the pineapple juice, soy sauce, brown sugar, ketchup, chicken broth, ginger, and garlic to create the marinade.
Reserve one cup of the marinade for basting later. Pour the rest over the chicken in a ziplock bag, seal it, and marinate in the refrigerator for at least three hours or overnight.
Preheat your grill to medium heat. Remove the chicken from the marinade and discard any remaining liquid. Grill the chicken for 6-8 minutes on each side until cooked through (internal temperature reaches 165°F). Baste with reserved marinade during the last five minutes of grilling.