Are some of the non-pork products (i.e. Fillet-o-Fish) being cross contaminated with pork?

Our Filet-o-Fish® patty is cooked separately from meat items in 100% vegetable oil. However, due to the design of the oil filtration system, during the oil filtering process, there is a small chance the oil used to cook our fish patties can come into contact with oil that has been used to cook chicken products. We therefore cannot guarantee cross-contamination will not occur but we have taken measures to minimise the amount of any cross-contamination.