Under good light that is indeed a wear mark in the plating. I thought it was a mark from rubber. The filter is marked made in Korea. I looked in the boxes of Emgo filters and they have the large black '0' ring but are unmarked and different than the one I just pulled. Have one BMW filter, standard Austrian job. According to th service log th po provided the oil and filter was last changed 1407 miles and 6 years ago. He stripped the cooler drain bolt at one point.