RedactedNarrative: Vessel #1 was struck from behind by vessel #2 causing extensive damage to vessel #1 stern section.  Damages were a bent stern pulpit, broken swim ladder, broken MOB Pole and loosening of the lifelines.  Vessel #2 sustained some minor scratches on the bow.  
  Vessel #2 was running w/ the auto pilot on when it struck vessel #1.  Failure of compass/auto pilot system caused vessel #2 to veer into vessel #1.  Compass system was fixed with new part installed.  No injuries were reported.